[clang] [llvm] [OpenACC] Switch Clang to use the Flang 'appertainment' rules for cla… (PR #135372)

[Valentin Clement バレンタイン クレメン via llvm-commits]

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

LGTM. I didn't go deep into the clang part since I don't have much knowledge there. There rest looks good. I'll merge https://github.com/llvm/llvm-project/pull/136341 as soon as the pre-commit ci is done. 

https://github.com/llvm/llvm-project/pull/135372