[media] v4l2: add const to argument of write-only s_tuner ioctl

This ioctl is defined as IOW, so pass the argument as const.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Alexey Klimov <klimov.linux@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/usb/tm6000/tm6000-video.c b/drivers/media/usb/tm6000/tm6000-video.c
index 49df753..b4618d7 100644
--- a/drivers/media/usb/tm6000/tm6000-video.c
+++ b/drivers/media/usb/tm6000/tm6000-video.c
@@ -1215,7 +1215,7 @@
 }
 
 static int vidioc_s_tuner(struct file *file, void *priv,
-				struct v4l2_tuner *t)
+				const struct v4l2_tuner *t)
 {
 	struct tm6000_fh   *fh  = priv;
 	struct tm6000_core *dev = fh->dev;
@@ -1293,18 +1293,14 @@
 }
 
 static int radio_s_tuner(struct file *file, void *priv,
-					struct v4l2_tuner *t)
+					const struct v4l2_tuner *t)
 {
 	struct tm6000_fh *fh = file->private_data;
 	struct tm6000_core *dev = fh->dev;
 
 	if (0 != t->index)
 		return -EINVAL;
-	if (t->audmode > V4L2_TUNER_MODE_STEREO)
-		t->audmode = V4L2_TUNER_MODE_STEREO;
-
 	v4l2_device_call_all(&dev->v4l2_dev, 0, tuner, s_tuner, t);
-
 	return 0;
 }