Revert 291b415c : [Misc] Use...

Revert 291b415c : [Misc] Use `LLVM_ENABLE_ABI_BREAKING_CHECKS` correctly (#94212)

The patch didn't consistently clean up `#ifdef LLVM_ENABLE_ABI_BREAKING_CHECKS` and '#if defined(LLVM_ENABLE_ABI_BREAKING_CHECKS)' paths, causing a lot of build failures