[media] uvcvideo: Drop unused ctrl member from struct uvc_control_mapping

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/uvc/uvc_ctrl.c

@@ -1880,7 +1880,6 @@ static int __uvc_ctrl_add_mapping(struct uvc_device *dev,
 	if (map->set == NULL)
 		map->set = uvc_set_le_value;
 
-	map->ctrl = &ctrl->info;
 	list_add_tail(&map->list, &ctrl->info.mappings);
 	uvc_trace(UVC_TRACE_CONTROL,
 		"Adding mapping '%s' to control %pUl/%u.\n",

drivers/media/video/uvc/uvcvideo.h

@@ -157,8 +157,6 @@ struct uvc_control_mapping {
 	struct list_head list;
 	struct list_head ev_subs;
 
-	struct uvc_control_info *ctrl;
-
 	__u32 id;
 	__u8 name[32];
 	__u8 entity[16];