[media] media: use entity.graph_obj.mdev instead of .parent

The struct media_entity has a .parent field that stores a pointer
to the parent struct media_device. But recently a media_gobj was
embedded into the entities and since struct media_gojb already has
a pointer to a struct media_device in the .mdev field, the .parent
field becomes redundant and can be removed.

This patch replaces all the usage of .parent by .graph_obj.mdev so
that field will become unused and can be removed on a later patch.

No functional changes.

The transformation was made using the following coccinelle spatch:

@@
struct media_entity *me;
@@

- me->parent
+ me->graph_obj.mdev

@@
struct media_entity *link;
@@

- link->source->entity->parent
+ link->source->entity->graph_obj.mdev

@@
struct exynos_video_entity *ve;
@@

- ve->vdev.entity.parent
+ ve->vdev.entity.graph_obj.mdev

Suggested-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/platform/exynos4-is/fimc-lite.c b/drivers/media/platform/exynos4-is/fimc-lite.c
index 2ce6704..11d2571 100644
--- a/drivers/media/platform/exynos4-is/fimc-lite.c
+++ b/drivers/media/platform/exynos4-is/fimc-lite.c
@@ -494,7 +494,7 @@
 	    atomic_read(&fimc->out_path) != FIMC_IO_DMA)
 		goto unlock;
 
-	mutex_lock(&me->parent->graph_mutex);
+	mutex_lock(&me->graph_obj.mdev->graph_mutex);
 
 	ret = fimc_pipeline_call(&fimc->ve, open, me, true);
 
@@ -502,7 +502,7 @@
 	if (ret == 0)
 		me->use_count++;
 
-	mutex_unlock(&me->parent->graph_mutex);
+	mutex_unlock(&me->graph_obj.mdev->graph_mutex);
 
 	if (!ret) {
 		fimc_lite_clear_event_counters(fimc);
@@ -535,9 +535,9 @@
 		fimc_pipeline_call(&fimc->ve, close);
 		clear_bit(ST_FLITE_IN_USE, &fimc->state);
 
-		mutex_lock(&entity->parent->graph_mutex);
+		mutex_lock(&entity->graph_obj.mdev->graph_mutex);
 		entity->use_count--;
-		mutex_unlock(&entity->parent->graph_mutex);
+		mutex_unlock(&entity->graph_obj.mdev->graph_mutex);
 	}
 
 	_vb2_fop_release(file, NULL);