Emulator Issues #5780
OGL: only update texture params if they changed
In the OGL backend, texture parameters will be set on every texture bind (so once per bound texture per indexed draw).
Texture params are part of the texture object, so binding one texture will also set the old texture params of this texture.
So this patch check the params on every bind and set them on changes.
At least my gpu driver (nvidia 310.14 amd64 linux) will not cache texture params, so there will be a noticeable speedup.