[TRITON] Moe a8w4 on gfx1250

[lburzawa]

Motivation

Add moe a8w4 on gfx1250.

Technical Details

New kernel for gfx1250 and updated wrapper to use either triton or gluon kernel.

Test Plan

UTs, IR/asm analysis on FFM, preliminary perf analysis on AM

Test Result

UTs pass

Submission Checklist

• Look over the contributing guidelines at https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.

[github-actions]

🏷️ CI Guide

Runs automatically on every PR:

• ✅ Pre-checks (submodule verification, code formatting)
• ✅ Aiter op tests (gfx942 + gfx950)
• ✅ Triton tests (only when aiter/ops/triton/** or related paths are changed)

Extended tests (opt-in via labels):

Label	Tests
ci:triton-355	Run Triton tests on MI355 in addition to MI325
ci:sglang	SGLang integration tests
ci:atom	ATOM benchmark (DeepSeek-R1 + GPT-OSS)
ci:vllm	vLLM benchmark
ci:all	All of the above

Add labels via the sidebar or gh pr edit 2494 --add-label <label>