media: vpbe_venc: potential uninitialized variable in ven_sub_dev_init()

Smatch complains that "venc" could be uninitialized.  There are a couple
of error paths where it looks like maybe that could happen.  I don't know
if it's really a bug, but it's reasonable to set "venc" to NULL and
silence the warning.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/platform/davinci/vpbe_venc.c

@@ -606,7 +606,7 @@ static int venc_device_get(struct device *dev, void *data)
 struct v4l2_subdev *venc_sub_dev_init(struct v4l2_device *v4l2_dev,
 		const char *venc_name)
 {
-	struct venc_state *venc;
+	struct venc_state *venc = NULL;
 
 	bus_for_each_dev(&platform_bus_type, NULL, &venc,
 			venc_device_get);