[clang] [llvm] [PowerPC] Add target feature validation for builtins in Sema (PR #187371)

[Maryam Moghadas via cfe-commits]

maryammo wrote:

It seems there are no tests that specifically trigger and verify the new `needs target feature` Sema error for PPC builtins.



https://github.com/llvm/llvm-project/pull/187371