improve explanatory comment about _SRGB backbuffers (#2230)
improve explanatory comment about _SRGB backbuffers (#2230)


emoon/bgfx,LWJGL-CI/bgfx,bkaradzic/bgfx,bkaradzic/bgfx,mendsley/bgfx,jdryg/bgfx,bkaradzic/bgfx,jdryg/bgfx,jdryg/bgfx,mendsley/bgfx,LWJGL-CI/bgfx,LWJGL-CI/bgfx,jdryg/bgfx,bkaradzic/bgfx,mendsley/bgfx,emoon/bgfx,LWJGL-CI/bgfx,emoon/bgfx