d3d: Fix silly typo in stencil handling.

Now it works.
Clear alpha only when clearing stencil.

Not sure if this will fix anything.
Warning fixes
d3d: Enable mipmapping.
d3d: Correct render-to-texture effects.

Was checking the corners wrong.
Add support for 24/8 textures in the GE debugger.
d3d: Support depth and stencil in the GE debugger.

But, not with our current depth surfaces.
d3d: Use INTZ if supported.

No performance impact on my card, and allows downloading depth/stencil
data.
d3d: Add a not-working experiment to blit depth.
Merge pull request #6909 from unknownbrackets/debugger

d3d: Use INTZ depth textures where supported
Merge pull request #6907 from unknownbrackets/d3d-mipmap

d3d: Enable mipmapping
d3d: Fix some issues with the vertex cache.
d3d: Fix vertex cache alpha flag tracking.
d3d: Use minihashing in the vertex cache.
d3d: Share the bounding box code.
Merge pull request #6910 from unknownbrackets/d3d9

d3d: Fix some vertex cache glitches, enable bounding box test
Restart to d3d9/gles preserving arguments.
Merge pull request #6911 from unknownbrackets/ui-tweaks

Restart to d3d9/gles preserving arguments