[clang] Diagnose misuse of the cleanup attribute (PR #80040)

[Shafik Yaghmour via cfe-commits]

https://github.com/shafik commented:

The failure of the Windows CI is due to a know problem w/ false detection of a virus. You can use `--allow-empty` to make an empty commit and restart the process. You have approval, so once it goes green you should be good to squash and merge.

https://github.com/llvm/llvm-project/pull/80040