[media] bttv: fix s_tuner for radio

Fix typo: g_tuner should have been s_tuner.

Tested with a bttv card.

Cc: stable@kernel.org
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/bt8xx/bttv-driver.c

@@ -3474,7 +3474,7 @@ static int radio_s_tuner(struct file *file, void *priv,
 	if (0 != t->index)
 		return -EINVAL;
 
-	bttv_call_all(btv, tuner, g_tuner, t);
+	bttv_call_all(btv, tuner, s_tuner, t);
 	return 0;
 }