[media] media-device: use unsigned ints on some places

The entity->num_pads are defined as u16. So, better to use an
unsigned int, as this prevents additional warnings when W=2
(or W=1 on some architectures).

The "i" counter at __media_device_get_topology() is also a
monotonic counter that should never be below zero. So,
make it unsigned too.
Suggested-by: Sakari Ailus <sakari.ailus@iki.fi>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/media-device.c

@@ -243,7 +243,8 @@ static long __media_device_get_topology(struct media_device *mdev,
 	struct media_v2_interface uintf;
 	struct media_v2_pad upad;
 	struct media_v2_link ulink;
-	int ret = 0, i;
+	unsigned int i;
+	int ret = 0;
 
 	topo->topology_version = mdev->topology_version;
 
@@ -609,7 +610,7 @@ EXPORT_SYMBOL_GPL(media_device_unregister);
 int __must_check media_device_register_entity(struct media_device *mdev,
 					      struct media_entity *entity)
 {
-	int i;
+	unsigned int i;
 
 	if (entity->function == MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN ||
 	    entity->function == MEDIA_ENT_F_UNKNOWN)
@@ -646,10 +647,10 @@ EXPORT_SYMBOL_GPL(media_device_register_entity);
  */
 void media_device_unregister_entity(struct media_entity *entity)
 {
-	int i;
 	struct media_device *mdev = entity->graph_obj.mdev;
 	struct media_link *link, *tmp;
 	struct media_interface *intf;
+	unsigned int i;
 
 	if (mdev == NULL)
 		return;