crtc: Move configured state to separate struct

To make it more reliable to distinguish between values that are read
from the backend implementation (which is likely to be irrelevant for
anything but the backend implementation), split out those values (e.g.
layout).

This changes the meaning of what was MetaCrtc::rect, to a
MetaCrtcConfig::layout which is the layout the CRTC has in the global
coordinate space.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1042

src/backends/meta-monitor-manager-private.h

@@ -24,6 +24,7 @@
 #define META_MONITOR_MANAGER_PRIVATE_H
 
 #include <cogl/cogl.h>
+#include <graphene.h>
 #include <libgnome-desktop/gnome-pnp-ids.h>
 
 #include "backends/meta-backend-private.h"
@@ -72,8 +73,7 @@ struct _MetaCrtcInfo
 {
   MetaCrtc                 *crtc;
   MetaCrtcMode             *mode;
-  int                       x;
-  int                       y;
+  graphene_rect_t           layout;
   MetaMonitorTransform      transform;
   GPtrArray                *outputs;
 };