[None][fix] Bump DeepGEMM to nv_dev HEAD for SM120 attention support

[lucifer1004]

The pinned DeepGEMM commit predates the SM120 implementations of the DSA/DSv4 indexer attention kernels (sm120_fp8_mqa_logits / sm120_fp8_paged_mqa_logits), so on SM120/SM121 the sparse-attention indexer fails with an unsupported-architecture error even though current DeepGEMM nv_dev supports the arch.

Bump the 3rdparty fetch pin to nv_dev a6b593d2826719dcf4892609af7b84ee23aaf32a, which carries the SM120 kernels. Validated as part of DeepSeek-V4 bring-up on RTX PRO 6000 Blackwell (the indexer dispatches and the model passes gsm8k gating at tp2/tp4).

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Summary by CodeRabbit

• Chores
  • Updated an underlying third-party component to a newer revision.
  • No changes to exported functionality or user-facing behavior.

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📥 Commits

Reviewing files that changed from the base of the PR and between 6929451 and 3b2f760.

📒 Files selected for processing (1)

• 3rdparty/fetch_content.json

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📝 Walkthrough

Walkthrough

The DeepGEMM dependency pin in 3rdparty/fetch_content.json is updated from commit 245dc5d6a5fe344c61505fe71011d203141d4479 to a6b593d2826719dcf4892609af7b84ee23aaf32a.

Changes

DeepGEMM Dependency Update

Layer / File(s)	Summary
Update DeepGEMM dependency pin 3rdparty/fetch_content.json	The deepgemm git_tag is updated to the new commit hash.

Estimated code review effort: 1 (Trivial) | ~2 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description explains the change, but it omits the required template sections for Description, Test Coverage, and PR Checklist.	Add the required template headings and fill in concise Description, Test Coverage, and PR Checklist sections.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title matches the change and follows the required [None][fix] format.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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