Revert "Fix `llvm-config` to emit the linker flag for the combined shared...

Revert "Fix `llvm-config` to emit the linker flag for the combined shared object built by autoconfig/make instead of the individual components."

It seems I was wrong thinking `autoconf`/`make` only installed shared libraries if configured with `--enable-shared`, even if `--disable-static` is present. I'll re-address with a followup patch.

This reverts commit r243297 for causing PR#24154.

llvm-svn: 244108