drm: add initial r500 drm support

This adds CP support for the r500 series of chips, and allows
accel 2D support on these chips with a new radeon driver.

Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --cc drivers/char/drm/drm_pciids.h
Simple merge

diff --cc drivers/char/drm/r300_cmdbuf.c
Simple merge

diff --cc drivers/char/drm/radeon_cp.c
Simple merge

diff --cc drivers/char/drm/radeon_drm.h
Simple merge

diff --cc drivers/char/drm/radeon_drv.h
Simple merge

diff --cc drivers/char/drm/radeon_state.c
Simple merge