drm: Consolidate crtc arrays in drm_atomic_state

It's silly to have 2 mallocs when we could tie these two together.

Also, Gustavo adds another one in his per-crtc out-fence patches. And
I want to add more stuff here for nonblocking commit helpers.

In the future we can use this to store a pointer to the preceeding
state, making an atomic update entirely free-standing. This will be
needed to be able to queue them up with a depth > 1.

Cc: Gustavo Padovan <gustavo@padovan.org>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1464818821-5736-12-git-send-email-daniel.vetter@ffwll.ch
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index c2ef42c..9450945 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1578,7 +1578,7 @@
 
 	for_each_crtc_in_state(state, crtc, crtc_state, i) {
 		crtc->state->state = state;
-		swap(state->crtc_states[i], crtc->state);
+		swap(state->crtcs[i].state, crtc->state);
 		crtc->state->state = NULL;
 	}