viotape: use noop_llseek

Some applications try to seek on tape devices
and fail if they return an error. Since we
want to change the default llseek action to
no_llseek, viotape needs to be changed to use
noop_llseek explicitly.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/drivers/char/viotape.c b/drivers/char/viotape.c
index 42f7fa4..442c3f5 100644
--- a/drivers/char/viotape.c
+++ b/drivers/char/viotape.c
@@ -804,6 +804,7 @@
 	.unlocked_ioctl =	viotap_unlocked_ioctl,
 	.open =			viotap_open,
 	.release =		viotap_release,
+	.llseek = 		noop_llseek,
 };
 
 /* Handle interrupt events for tape */