Arm backend: Add MXFP4/MXFP6 linear support

[martinlsm]

Add support for running torch.nn.Linear modules in MXFP4E2M1,
MXFP6E3M2 and MXFP6E2M3. Update the MXFPOpConfig to support
the data types.

Since torch lacks FP6 datatypes, the string-based definitions in
torchao are used as a workaround.

The custom TOSA op receives a new argument called
str weight_payload_dtype which tells which dtype is used for the
weights. The weight tensor itself does not contain this info since the
FP4 and FP6 formats are storted into uint8 tensors.

The CAST_TO_BLOCK_SCALED required to transform activations from/to MXFP
is also updated to support the new datatype. Its custom TOSA op gets a
str output_dtype similar to the weight_payload_dtype for the MXFP
linear op.

cc @digantdesai @freddan80 @per @zingo @oscarandersson8218 @mansnils @Sebastian-Larsson @robell @rascani

[pytorch-bot]

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❌ 7 New Failures, 3 Cancelled Jobs, 7 Unrelated Failures, 29 Unclassified Failures

As of commit 65128df with merge base 0da9ca3 ():

NEW FAILURES - The following jobs have failed:

• Apple / build-demo-ios / macos-job (gh)
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• Apple / build-frameworks-ios / macos-job (gh)
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• pull / test-lora-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 7e50c977bc64945d89c99eeed8168a0d0b3cadb54fa8f599627e9bb2362038ce /exec failed with exit code 1
• pull / test-lora-multimethod-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 7dc4edc8ccada764a69ea2aa96f99db810a5634d4670c6b6bced37935def4ded /exec failed with exit code 1
• pull / test-phi-3-mini-runner-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 892bd0b7efd327d59a4387e33fbd4c8a7994f232d38e3f1184dcdcdb61069ffd /exec failed with exit code 1
• pull / test-voxtral-realtime-xnnpack-linux / linux-job (gh)
  RuntimeError: Command docker exec -t d2462142d422e91d649ade3ca004d46470218e76033857e9abfd5f2ff458c4b7 /exec failed with exit code 1
• trunk / test-models-macos-mps / macos-job (gh)
  The process '/usr/bin/git' failed with exit code 1

UNCLASSIFIED FAILURES - DrCI could not classify the following jobs because the workflow did not run on the merge base. The failures may be pre-existing on trunk or introduced by this PR:

• pull / test-coreml-bc-macos (macos-m1-stable) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-coreml-delegate / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/opt/homebrew/bin/git' failed with exit code 128
• trunk / test-custom-ops-macos (cmake) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-huggingface-transformers-macos (distilbert|coreml_fp32_gpu|--quantize) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/opt/homebrew/bin/git' failed with exit code 128
• trunk / test-huggingface-transformers-macos (olmo-1b|coreml_fp32_gpu|--quantize) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/opt/homebrew/bin/git' failed with exit code 128
• trunk / test-huggingface-transformers-macos (smollm2-135m|coreml_fp32_gpu|--quantize) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/opt/homebrew/bin/git' failed with exit code 128
• trunk / test-llama-runner-mac (fp32, mps) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-llama-torchao-lowbit / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-coreml (dl3) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-coreml (edsr) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-coreml (efficient_sam) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-coreml (emformer_join) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-coreml (emformer_transcribe) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-coreml (ic3) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-coreml (ic4) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-coreml (mv2) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-coreml (mv3) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-coreml (resnet50) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-coreml (vit) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-cpu (efficient_sam, portable) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-cpu (ic4, xnnpack-quantization-delegation) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-cpu (llama, portable) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-cpu (llama2, xnnpack-quantization-delegation) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-cpu (mobilebert, xnnpack-quantization-delegation) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-cpu (mv3, portable) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-cpu (vit, xnnpack-quantization-delegation) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-models-macos-cpu (w2l, xnnpack-quantization-delegation) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-selective-build-macos (cmake) / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1
• trunk / test-static-llama-ane / macos-job (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)
  The process '/usr/bin/git' failed with exit code 1

CANCELLED JOBS - The following jobs were cancelled. Please retry:

• pull / unittest / linux / linux-job (gh)
  ##[error]The operation was canceled.
• pull / unittest-editable / linux / linux-job (gh)
  ##[error]The operation was canceled.
• trunk / unittest-release / linux / linux-job (gh)
  ##[error]The operation was canceled.

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• trunk / test-models-windows (mobilebert, portable) / windows-job (gh) (matched win rule in flaky-rules.json)
  ##[error]The operation was canceled.

BROKEN TRUNK - The following jobs failed but was present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• pull / test-llama-runner-qnn-linux (fp32, qnn_16a16w, qnn) / linux-job (gh) (trunk failure)
• pull / unittest / macos / macos-job (gh) (trunk failure)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 1
• pull / unittest / windows / windows-job (gh) (trunk failure)
  examples/models/test/test_export.py::ExportTest::test_efficient_sam_export_to_executorch
• pull / unittest-editable / macos / macos-job (gh) (trunk failure)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 1
• trunk / test-llama-runner-qnn-linux (fp32, qnn_16a16w, qnn) / linux-job (gh) (trunk failure)
• trunk / unittest-release / macos / macos-job (gh) (trunk failure)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 1

This comment was automatically generated by Dr. CI and updates every 15 minutes.

[martinlsm]

@pytorchbot label ciflow/trunk

[martinlsm]

@pytorchbot label "partner: arm"

[martinlsm]

@pytorchbot label "release notes: arm"

[zingo]

OK to merge if tests pass and Mypy error is fixed
nss test fails in unrelated