[clang] [clang] __builtin_os_log_format has incorrect PrintfFormat Attribute argument (PR #178320)

[Aaron Ballman via cfe-commits]

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

LGTM though I think we can simplify the test RUN lines a bit to make it more clear what's being tested.

https://github.com/llvm/llvm-project/pull/178320