video-rice: Merged more files with upstream.

The following files are now identical:
 - OGLExtCombiner.h
 - OGLTexture.h
 - RenderExt.cpp
 - RenderTexture.cpp

As of upstream commit:
https://bitbucket.org/littleguy77/mupen64plus-video-rice/commits/8148bd05b8aa92e5b4b466f16c385565f6120923