[clang] [Clang][Basic] Add `__has_feature` checks for CFI sanitizers (PR #151348)

[via cfe-commits]

moorabbit wrote:

Added a `REQUIRES: target={{x86_64.*-linux.*}}` in my last commit to fix the test failure on windows.
Since this PR is only adding a preprocessor feature and not something platform specific, I think it's fine to only test on x86_64-linux and skip other targets?

https://github.com/llvm/llvm-project/pull/151348