V4L/DVB: videobuf: add ext_lock argument to the queue init functions

Add an ext_lock argument to the videobuf init functions. This allows
drivers to pass the vdev->lock pointer (or any other externally held lock)
to videobuf. For now all drivers just pass NULL.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/common/saa7146_video.c b/drivers/media/common/saa7146_video.c
index a212a91..741c573 100644
--- a/drivers/media/common/saa7146_video.c
+++ b/drivers/media/common/saa7146_video.c
@@ -1386,7 +1386,7 @@
 			    V4L2_BUF_TYPE_VIDEO_CAPTURE,
 			    V4L2_FIELD_INTERLACED,
 			    sizeof(struct saa7146_buf),
-			    file);
+			    file, NULL);
 
 	return 0;
 }