[clang] [Clang]: enhance handling of [[deprecated]] attribute diagnostics for local variables (PR #113575)

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https://github.com/Sirraide approved this pull request.

LGTM

On the issue for this, there was some discussion about the fact that the standard might disallow deprecating local variables at some point, but so long as we (still) allow that, it only makes sense to actually diagnose the deprecation as well considering that it seems to be straight-forward enough to implement.

https://github.com/llvm/llvm-project/pull/113575