architecture in place (Lacks actual DMA submission (The easy part,
really...)) so it's not done yet, but I promised people that done or
not, I'd do a check-in of this...
- Fix old-style DMA for gamma driver (please test).
- Pull out IRQ handling into drm_dma.h (please test on i810, gamma).
- Lots of general cleanups, remove compiler warnings etc.