[Clang][OpenMP] libompd: get libomp hwloc includedir by target_link_libraries

When hwloc is used and is installed outside of the default paths, the omp CMake target
needs to provide the needed include path thru the CMake target by adding it with
target_include_directories to it, so libompd gets it as well when it defines it's cmake
target using target_link_libraries.

As suggested in D122667

Reviewed By: ye-luo

Differential Revision: https://reviews.llvm.org/D123888