Support memsets of framebuffers as uploads.

Technically should clear stencil too... maybe it'd be better to handle
separately.
Support swizzled framebuffer downloads.

Used in God Eater 2 when showing the load save screen.
Apply unsupported blending modes in the shader.

This handles unsupported fixed color combinations, alpha doubling, etc.
Where possible, tries to avoid it - it means using a blit (without the
framebuffer fetch extension), which can slow things down a lot with tons
of drawcalls.
Double using multiply not add, should be fine.
Skip a few more fixa/fixb combos.
Log when blitting a ton per frame, it can get slow.
Remove outdated comment.

Was all lies.
Oops, typo.
Set a bit to account for fixa/fixb/etc. logic.
Unbind the fbo texture when it's not used.

Just in case there are problems with decimating it or etc.
Ignore the funcs for min/max/absdiff.

Seems from reports that they are indeed ignored, just wanted to verify.
Disable the scissor test around blits.

Because it applies.
Make sure to rebind a texture after changing it.
sceio:Remove fix Buzz Ultimate Music Quiz Crash Sporadically code

Now no need the code.
link #4497
Use a separate func for gpu memset().
Don't savestate replacement funcs.

This makes it so we can reorder them as we like, which is nicer, and also
makes sure there won't be weird compatibility problems or etc.
Symbian: Fix a crash when PSMF version is set to basic. Just do nothing instead. Fixes #6103