Clang 17 resource-dir cannot be found on Fedora 39

With the LLVM/CLang 17 package provided in the official Fedora 39 sources, the "Clang Resource Directory" moves from /usr/lib64/clang/<version> to /usr/lib/clang/<version> while the LibClang remains in /usr/lib64/libclang.so, making the code to locate it insufficient (see official notes).

It looks like the proper way of determining the resource directory would be to invoke clang --print-resource-dir for the clang-executable in use.

I will have a look on how to implement this. and see if this can be queried from the LibCLang.