Revert "[PGO] Fix __llvm_profile_raw_version linkage in MACHO IR...

Revert "[PGO] Fix __llvm_profile_raw_version linkage in MACHO IR instrumentation generates a COMDAT symbol __llvm_profile_raw_version to overwrite the same symbol in profile run-time to distinguish IR profiles from Clang generated profiles. In MACHO, LinkOnceODR linkage is used due to the lack of COMDAT support."

This reverts commits r268969, r268979 and r268984. They had target specific test
in generic directories without the correct specifiers and made it hard for us to
come up with a good solution by rapidly committing untested changes.

This test needs to be in a target specific directory or have the correct REQUIRED
identifier.

llvm-svn: 269027