fix: clover: LLVM 18 renamed/moved CGFT_*, update compat layer

fix: clover: LLVM 18 renamed/moved CGFT_*, update compat layer

LLVm renamed and moved the CGFT_* stuff, we need to update the clover
compat header to follow suit.

Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/9833
Reference: https://github.com/llvm/llvm-project/commit/0a1aa6cda2758b0926a95f87d39ffefb1cb90200
Signed-off-by: Kai Wasserbäch <kai@dev.carbon-project.org>
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25586>