media: v4l2-ioctl.c: fix missing unlock in __video_do_ioctl()

If dev_debug was active, then the code could return without unlocking the
core mutex. Replace the return with a 'goto unlock' to ensure proper unlocking.

Fixes: 73a11062 ("v4l2-core: push taking ioctl mutex down to ioctl handler")
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/v4l2-core/v4l2-ioctl.c

@@ -2777,7 +2777,7 @@ static long __video_do_ioctl(struct file *file,
 	if (dev_debug & (V4L2_DEV_DEBUG_IOCTL | V4L2_DEV_DEBUG_IOCTL_ARG)) {
 		if (!(dev_debug & V4L2_DEV_DEBUG_STREAMING) &&
 		    (cmd == VIDIOC_QBUF || cmd == VIDIOC_DQBUF))
-			return ret;
+			goto unlock;
 
 		v4l_printk_ioctl(video_device_node_name(vfd), cmd);
 		if (ret < 0)