Add Qwen3-Coder SGLang benchmarks

[haofrank]

Title

Add Qwen3-Coder 480B SGLang benchmark configurations for MI355X

Summary

Add single-node SGLang benchmark configurations for Qwen3-Coder 480B A35B on MI355X:

• amd/Qwen3-Coder-480B-A35B-Instruct-MXFP4
• Qwen/Qwen3-Coder-480B-A35B-Instruct-FP8

Both configurations use TP4 and AITER kernels. The FP8 configuration also uses FP8 KV cache with a page size of 32.

Configuration

• GPU: 4× MI355X
• Tensor parallelism: TP4
• AITER: enabled
• Workload: ISL/OSL 1024/1024, concurrency 32
• Random range ratio: 0.8
• FP8 KV cache: fp8_e4m3

Validation

Both configurations successfully completed 320/320 benchmark requests.

Model precision	Request throughput	Output throughput	Mean TTFT	Mean TPOT	Mean E2E
MXFP4	1.93 req/s	1,783.72 tok/s	179.10 ms	17.35 ms	16.21 s
FP8	1.48 req/s	1,363.58 tok/s	229.74 ms	22.69 ms	21.18 s

[ChengYao-amd]

LGTM