V4L/DVB (10912): vivi: fix compile warning.

Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/vivi.c

@@ -1406,7 +1406,7 @@ static int __init vivi_create_instance(int inst)
  */
 static int __init vivi_init(void)
 {
-	int ret, i;
+	int ret = 0, i;
 
 	if (n_devs <= 0)
 		n_devs = 1;