[clang] [WebAssembly] Clang support for acquire-release atomics (PR #184901)

[Heejin Ahn via cfe-commits]

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

I think we should add new features to bleeding-edge CPU here:
https://github.com/llvm/llvm-project/blob/fb7d25556a3ac6b48deaa63a9195cf47b830e372/clang/lib/Basic/Targets/WebAssembly.cpp#L194-L206
and here:
https://github.com/llvm/llvm-project/blob/fb7d25556a3ac6b48deaa63a9195cf47b830e372/clang/test/Preprocessor/wasm-target-features.c#L208-L223

Otherwise LGTM

https://github.com/llvm/llvm-project/pull/184901