[clang] [llvm] [PowerPC][AIX] Support #pragma comment copyright for AIX (PR #178184)

[Hubert Tong via cfe-commits]

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

LGTM (for the front-end) with specific suggestions to address code-style issues.

@tonykuttai, the general take-away from this round of review is that code comments should provide value to the understanding of the code where it appears and that said value needs to be balanced against the drafting, review, and maintenance burden of having the comment.

Especially for comments of a "design overview" nature, the information can instead be added to PR descriptions or separate documentation artifacts.

https://github.com/llvm/llvm-project/pull/178184