[llvm] [AIX] Support per global code model. (PR #79202)

[zhijian lin via llvm-commits]

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

I put other two small comment. I do not have further comment on the patch, please address zhengchen's comment and wait for zhengchen happy with the PR.

https://github.com/llvm/llvm-project/pull/79202