rm openxr_oculus.h;

It is now an empty file in the Oculus OpenXR SDK, because the
corresponding extensions have been integrated into the main OpenXR SDK.

src/modules/headset/headset_openxr.c

@@ -45,9 +45,6 @@ typedef XID GLXContext;
 #define XR_NO_PROTOTYPES
 #include <openxr/openxr.h>
 #include <openxr/openxr_platform.h>
-#ifdef __ANDROID__
-#include <openxr/openxr_oculus.h>
-#endif
 
 #define XR(f) handleResult(f, __FILE__, __LINE__)
 #define XR_INIT(f) if (XR_FAILED(f)) return openxr_destroy(), false;