Add padding to cshuffle epilogue to avoid bank conflict

[ThomasNing]

Proposed changes

Added the padding to CShuffle Epilogue to avoid the bank conflicts of 64. Synced up and learned from the internal repo.

Checklist

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• I have added tests relevant to the introduced functionality, and the unit tests are passing locally
• I have added the test to REGRESSION_TESTS list defined at the top of CMakeLists.txt in tests/CMakeLists.txt, IF the test takes more than 30 seconds to run.
• I have added inline documentation which enables the maintainers with understanding the motivation
• I have removed the stale documentation which is no longer relevant after this pull request
• (If this change is user-facing) I have added release notes which provide the end users with a brief summary of the improvement from this pull request
• I have run clang-format on all changed files
• Any dependent changes have been merged

Discussion

If this is a relatively large or complex change, feel free to start a discussion by explaining why you chose the solution you did and what alternatives you considered

[ThomasNing]

@tenpercent For your reference~

[Copilot]

Pull request overview

This PR adds padding to the CShuffleEpilogue to avoid bank conflicts on AMD GPUs, specifically targeting 64-way bank conflicts. The changes synchronize the implementation with an internal repository and modify the LDS (Local Data Store) block descriptor generation logic.

Changes:

• Added conditional padding logic for GFX950 architecture to avoid bank conflicts
• Implemented multi-layer LDS block descriptor transformations for both RowMajor and ColumnMajor layouts
• Changed tile distribution pattern from thread_raked to warp_raked

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