[clang] [clang][darwin] macOS no longer infers a minimum deployment version from the OS version (PR #181958)

[Cyndy Ishida via cfe-commits]

cyndyishida wrote:

Can you please attach radars to the commit messages if there is a relevant one? its customary to just add a link at the end of the message. 

https://github.com/llvm/llvm-project/pull/181958