new PowerVR2 VRAM test

I added another test to the hw tests section. It tests that the emulator implemented the VRAM memory bus correctly.

TBH this test is kinda pedantic and I doubt the things it tests actually matter. I made this a few years ago becuase I was convinced I had found a game which relies upon a very specific hardware quirk of the VRAM bus, but eventually that turned out to be incorrect.

So this test is kind-of a waste of time but it's something I made and it does test for actual hardware quirks that could otherwise be easily overlooked by an emulator so I might as well keep it around. I'm actually using it right now to test some that some optimizations I'm making don't break VRAM writes so it's not totally useless. Sometimes it's useful to have a test that does lots of uninteresting things just to prove or disprove that your emulator is sane.

also happy thanksgiving, i guess.