This update for llvm17 fixes the following issues:

- Add symbol versions to libclang-cpp.so similar to libLLVM.so. This is
required when multiple versions of the library are loaded into the same
process. (boo#1219405, boo#1221183, boo#1233220)
- Require libffi when we build openmp for offloading.
- Correct target name for libomptarget in file list (backport from llvm18)
- Enable lldb on s390x and ppc64le (boo#1232906).
- Fix build with GCC 14 on aarch64. (boo#1229868, gh#llvm/llvm-project#78691)
- Use old conflicts/provides for python3-clang on Leap.