Fixed some bugs in OpenVR and OpenXR mode.

src/headset/emulated_headset.cpp

src/headset/headset.cpp

src/headset/headset.hpp

src/headset/openvr_headset.cpp

src/headset/openvr_headset.hpp

src/headset/openxr_headset.cpp

src/headset/openxr_headset.hpp

src/headset/remote_headset.cpp

src/vr_application.cpp