[amdgpu-arch] Fix build of amdgpu-arch with CLANG_LINK_CLANG_DYLIB

The function clang_target_link_libraries must only be used with real
Clang libraries; with CLANG_LINK_CLANG_DYLIB, it will instead link in
clang-cpp. We must use the standard CMake target_link_libraries for
the HSA library.