* video_core/renderer_opengl: Move SurfaceParams into its own file
Some of its enums are needed outside of the rasterizer cache
and trying to use it caused circular dependencies.
* video_core/renderer_opengl: Overhaul the texture filter framework
This should make it less intrusive.
Now texture filtering doesn't have any mutable global state.
The texture filters now always upscale to the internal rendering resolution.
This simplifies the logic in UploadGLTexture and it simply takes the role of BlitTextures at the end of the function.
This also prevent extra blitting required when uploading to a framebuffer surface with a mismatched size.
* video_core/renderer_opengl: Use generated mipmaps for filtered textures
The filtered guest mipmaps often looked terrible.
* core/settings: Remove texture filter factor
* sdl/config: Remove texture filter factor
* qt/config: Remove texture filter factor
Marshall Mohror