[clang] [compiler-rt] [llvm] [PGO] Initialize GCOV Writeout and Reset Functions in the Runtime on AIX (PR #108570)

[Hubert Tong via cfe-commits]

https://github.com/hubert-reinterpretcast approved this pull request.

LGTM with minor comment; thanks!

https://github.com/llvm/llvm-project/pull/108570