Given that we're building `--with=compat_build`, when we don't
exclude the patches, the following logic will try to apply all
patches to clang even if they are meant for clang-tools-extra:
```
%if %{with compat_build}
%autosetup -n %{clang_srcdir} -p2
%else
```
I'm not willing to patch the %auto... part because I fear to break
stuff. Both ways work.