Pkg-config files generated by CMake do not include the WSL stubs

[SomeoneSerge]

Pkg-config files generated by CMake do not include the stubs:

DirectX-Headers/CMakeLists.txt

Line 96 in 7fc7184

join_paths(DIRECTX_INCLUDEDIR_FOR_PKG_CONFIG "\${prefix}" "${CMAKE_INSTALL_INCLUDEDIR}")

To contrast, cflags generated by meson include .../wsl/stubs: Cflags: -I${includedir} -I${includedir} -I${includedir}/wsl/stubs -I${includedir}/directx.

Note that cmake rules do include a conditional target_link_libraries and the generated directx-headers-config.cmake is in fact correct. If only the pkg-config was somehow derived from get_target_property(... DirectX-Headers INTERFACE_INCLUDE_DIRECTORIES) (non-trivial because of generator expressions) the output would've been correct.