[libc-commits] [libc] [llvm] [libc] Remove obsolete LIBC_HAS_BUILTIN macro (PR #86554)

[Nick Desaulniers via libc-commits]

nickdesaulniers wrote:

> > I'll wait for presubmit results and @gchatelet 's feedback when he's comes back online, but LGTM.
> 
> There's some bazel breakage from this change. Let me figure out what's going on.

Ok, I needed to remove the include of `src/__support/macros/config.h` from:
- libc/src/__support/CPP/type_traits/add_pointer.h
- libc/src/__support/CPP/type_traits/decay.h
- libc/src/__support/CPP/type_traits/is_trivially_copyable.h

Then the build succeeds.  I was hoping to save all that cleanup for #86579, but I think they should just be cleaned up in this PR.

https://github.com/llvm/llvm-project/pull/86554