drm/i915: Use plane state for primary plane updates.

drm/i915: Use plane state for primary plane updates.

Pass in the atomic states to allow for proper updates.
This removes uses of intel_crtc->config and direct access
to plane->state.

This breaks the last bit of kgdboc, but that appears to be dead code.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452164052-21752-7-git-send-email-maarten.lankhorst@linux.intel.com
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>