kms: Mark mode set updates as such

This is currently unused, but will be later used to distinguish betwen
per frame/CRTC updates and device wide ones.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2777>

src/backends/native/meta-kms-types.h

@@ -80,6 +80,7 @@ typedef enum _MetaKmsUpdateFlag
 {
   META_KMS_UPDATE_FLAG_NONE = 0,
   META_KMS_UPDATE_FLAG_TEST_ONLY = 1 << 0,
+  META_KMS_UPDATE_FLAG_MODE_SET = 1 << 1,
 } MetaKmsUpdateFlag;
 
 typedef enum _MetaKmsPlaneType MetaKmsPlaneType;

src/backends/native/meta-renderer-native.c

@@ -873,8 +873,9 @@ post_mode_set_updates (MetaRendererNative *renderer_native)
                                            NULL,
                                            NULL);
 
-      feedback = meta_kms_device_process_update_sync (kms_device, kms_update,
-                                                      META_KMS_UPDATE_FLAG_NONE);
+      feedback =
+        meta_kms_device_process_update_sync (kms_device, kms_update,
+                                             META_KMS_UPDATE_FLAG_MODE_SET);
     }
 }