[libclc] [libclc] Remove unused and incorrect pkgconf file (PR #185654)

[Karol Herbst via cfe-commits]

karolherbst wrote:

> > > Can you please elaborate on that?
> > 
> > 
> > I don't fully know how it's linked up, you still need to pass this flag, but it's supposed to link relative to the compiler. https://github.com/llvm/llvm-project/blob/main/clang/include/clang/Options/Options.td#L1492
> 
> I don't think this would be relevant for mesa, as this seems to be hooked up to `-mlink-builtin-bitcode`, while mesa uses the spv files, not the bc files.
> 
> I assume mesa will have to manually look this up in the clang resource directory now, instead of fetching the path from pkgconfig.
> 
> cc @karolherbst

probably a good reason to land something like this: https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34834

https://github.com/llvm/llvm-project/pull/185654