media: staging: media: imx: imx7-media-csi: Don't initialize unused fields

The imx_media_dev structure contains three fields that are not used by
this driver or any helper code that it calls. Don't initialize them.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/staging/media/imx/imx7-media-csi.c

@@ -1821,8 +1821,6 @@ static int imx7_csi_media_dev_init(struct imx7_csi *csi)
 	imxmd->md.ops = &imx7_csi_media_ops;
 	imxmd->md.dev = csi->dev;
 
-	mutex_init(&imxmd->mutex);
-
 	imxmd->v4l2_dev.mdev = &imxmd->md;
 	strscpy(imxmd->v4l2_dev.name, "imx-media",
 		sizeof(imxmd->v4l2_dev.name));
@@ -1838,10 +1836,6 @@ static int imx7_csi_media_dev_init(struct imx7_csi *csi)
 		goto cleanup;
 	}
 
-	INIT_LIST_HEAD(&imxmd->vdev_list);
-
-	v4l2_async_nf_init(&imxmd->notifier);
-
 	return 0;
 
 cleanup: