ggml-hexagon: add Q4_1 support

[max-krasnyansky]

This PR adds support for Q4_1 data type for MUL_MAT operations in the Hexagon backend.

Changes:

• Added HTP_TYPE_Q4_1 and HTP_TYPE_Q8_1 mappings and their x4x2 constants.
• Handled tensor buffering logic (get_alloc_size) to accommodate the QK_Q4_1x4x2 (160 bytes) and QK_Q8_1x4x2 block dimensions.
• Added repack_q4_1_q4x4x2 and repack_q8_1_q8x4x2 pack/unpack functions to ggml-hexagon.cpp, modifying the buffer assignment operations (set_tensor and get_tensor) accordingly.
• Introduced dynamic quantize rows logic quantize_row_f32_q8_1x4x2 for FP32 activations in matmul-ops.c, taking into account offset calculations.
• Integrated HVX vector dot kernels vec_dot_q4_1x4x2_q8_1x4x2_1x1, 2x1, and 2x2, utilizing the newly created minimum layout offsets format.
• Mapped Q4_1 type into the supported types matrix in ggml_hexagon_supported_mul_mat and ggml_hexagon_supported_mul_mat_id.
• Configured HMX support for HTP_TYPE_Q4_1, handling its corresponding minimum offset logic directly within the dequantization pass hmx-matmul-ops.c.

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PR created automatically by Jules for task 12614708629588356175 started by @max-krasnyansky

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