add WIN32/WGL

src/xrt/auxiliary/CMakeLists.txt

src/xrt/auxiliary/ogl/wgl_api.c

src/xrt/auxiliary/ogl/wgl_api.h

src/xrt/compositor/CMakeLists.txt

src/xrt/compositor/client/comp_gl_memobj_swapchain.c

src/xrt/compositor/client/comp_gl_win32_client.c

src/xrt/compositor/client/comp_gl_win32_client.h

src/xrt/compositor/client/comp_gl_win32_glue.c

src/xrt/include/xrt/xrt_gfx_win32.h

src/xrt/state_trackers/oxr/CMakeLists.txt

src/xrt/state_trackers/oxr/oxr_api_verify.h

src/xrt/state_trackers/oxr/oxr_objects.h

src/xrt/state_trackers/oxr/oxr_session.c

src/xrt/state_trackers/oxr/oxr_session_gfx_gl_win32.c

src/xrt/state_trackers/oxr/oxr_swapchain.c

src/xrt/state_trackers/oxr/oxr_swapchain_gl.c

src/xrt/state_trackers/oxr/oxr_swapchain_vk.c

src/xrt/state_trackers/oxr/oxr_verify.c