Rice backport -  remove GL_ARB_texture_env_combine and GL_EXT_texture_env_combine chec…

…ks and consider them always true as they both are part of OGL1.3, also clean the constant names - https://github.com/Narann/mupen64plus-video-rice/commit/9de00e9331e8919ddb232d266d8db1b3589f739b