[TRITON] Fix Assert in Triton fused_kv_cache

[leonling-ll]

Assertion in triton kernel fused_qk_rope_reshape_and_cache: t == tk == tv and t_slot <= tk would be inconsistant the logic in _fused_qk_rope_reshape_and_cache_kernel.
In which pid could be greater than TxQH, while the assertion assume the launch grid is smaller or equal to TxQH (n_pid = t * qh + (t_slot - t) * kh)

This makes CI failing: https://github.com/ROCm/ATOM/actions/runs/27060334232/job/79872120485#step:22:537

This PR aims to fix it and fix some typo.

[github-actions]

🏷️ CI Guide

Runs automatically on every PR:

• ✅ Pre-checks (submodule verification, code formatting)
• ✅ Aiter op tests (gfx942 + gfx950)
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Extended tests (opt-in via labels):

Label	Tests
ci:triton-300x	Run an additional Triton test job on MI300X in PRs; main branch always runs both MI35X and MI300X
ci:sglang	SGLang integration tests: DeepSeek-R1-MXFP4 accuracy, Qwen 3.5 accuracy
ci:atom	ATOM benchmark: DeepSeek-R1-0528, GPT-OSS-120B
ci:atom_full	ATOM accuracy suite for PR and main models from ATOM models_accuracy.json
ci:vllm	vLLM benchmark: GPT-OSS-120B, DeepSeek-R1-0528, Kimi-K2.5
ci:all	All standard extended tests (excludes ci:atom_full)

Only add ci:atom_full for FlyDSL or Triton upgrades.
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[JiaoliangYu]

looks good to merge

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