lima: handle early-z and pixel kill better
[1] calls bit 12 of aux0 'pixel kill' which is likely forward pixel kill described in [2]. Blob sets this bit if early-z is enabled and blending is disabled and colormask is RGBA.
Bit 8 seems to be always enabled with bit 9 (early-z).
Let's mimic blob behavior.
[1] https://web.archive.org/web/20171026123213/http://limadriver.org/Render_State/ [2] https://community.arm.com/developer/tools-software/graphics/b/blog/posts/killing-pixels---a-new-optimization-for-shading-on-arm-mali-gpus
Signed-off-by: Vasily Khoruzhick anarsoul@gmail.com