[llvm] [clang] [Clang] Emit TBAA info for enums in C (PR #73326)

[Paul Walker via cfe-commits]

https://github.com/paulwalker-arm approved this pull request.

This looks broadly good to me.  I suggest reverting the LangRef change because it doesn't add any new information relevant to LLVM IR.

https://github.com/llvm/llvm-project/pull/73326