[optimization] TextureCacheBase: Slightly loosen the requirements for reusing mipmapped textures
[cleanup] [bugfix] TextureCacheBase: Cleanup and simplify mipmapping logic. Possibly fixes a bug or two.
[cleanup] TextureCache: Kill the autogen_mipmap parameter
[cleanup] Vastly clean up backend-specific sampler state logic.
[bugfix] DX9::TextureCache: Use max_lod instead of min_lod where necessary.
[bugfix] Properly decode lod_bias.
[bugfix] Make sure to specify the correct max lod level.
Merge branch 'mipmap_fixes'.
Revert "[bugfix] DX9::TextureCache: Use max_lod instead of min_lod where necessary."

This reverts commit 6c8a22de24e1e374c4357ca653ac584c8a6adfac.