[BugFix][CPU] Fix TorchSDPABackendImpl doesn't have use_irope

[LucasWilkinson]

Temp fix to avoid potential error with TorchSDPABackendImpl not saving iRoPE; preferred fix is: #21188 but putting this up this simple fix incase that doesnt make it in time for the cut

[github-actions]

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[gemini-code-assist]

Code Review

This pull request provides a temporary fix for a potential AttributeError when accessing use_irope on an attention implementation. The change uses getattr to safely access the attribute with a default value, which is a robust and Pythonic approach. The fix is correct and effectively prevents the runtime error as intended. Given the context that this is a temporary solution, the change is appropriate.

[LucasWilkinson]

Holding off the merge for now since this is not needed if #21188 lands

[DarkLight1337]

Oops sorry I missed this comment, was working from latest to oldest PRs