drm/i915: Add main atomic entrypoints (v2)

Add the top-level atomic entrypoints for check/commit.  These won't get
called yet; we still need to either enable the atomic ioctl or switch to
using the non-transitional atomic helpers for legacy operations.

v2:
 - Use plane->pipe rather than plane->possible_crtcs while ensuring that
   only a single CRTC is in use.  Either way will work fine since i915
   drm_plane's are always tied to a single CRTC, but plane->pipe is
   slightly more intuitive. (Ander)
 - Simplify crtc/connector checking logic. (Ander)

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Ander Conselvan de Oliveira <conselvan2@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 3d65e8b..18f167b 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1249,6 +1249,13 @@
 void intel_tv_init(struct drm_device *dev);
 
 /* intel_atomic.c */
+int intel_atomic_check(struct drm_device *dev,
+		       struct drm_atomic_state *state);
+int intel_atomic_commit(struct drm_device *dev,
+			struct drm_atomic_state *state,
+			bool async);
+
+/* intel_atomic_plane.c */
 struct intel_plane_state *intel_create_plane_state(struct drm_plane *plane);
 struct drm_plane_state *intel_plane_duplicate_state(struct drm_plane *plane);
 void intel_plane_destroy_state(struct drm_plane *plane,