[clang] [Clang][Comments] Attach comments to decl even if preproc directives are in between (PR #88367)

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hdoc wrote:

This is rebased onto the latest rev of the main branch and should be ready to go. We do not have commit permissions, so @AaronBallman could you please help merge this in? Thank you :) 

https://github.com/llvm/llvm-project/pull/88367