DRM core provide helper to access crtc state.
Signed-off-by: NAndrzej Hajda <a.hajda@samsung.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1458045960-25193-1-git-send-email-a.hajda@samsung.com