drm/radeon/kms/atom: rework crtc modeset

- clean up tv timing handling
- unify SetCRTC_Timing and SetCRTC_UsingDTDTiming

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
3 files changed