[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/pci/ivtv/ivtv-ioctl.c b/drivers/media/pci/ivtv/ivtv-ioctl.c
index e6258b6..852f11e 100644
--- a/drivers/media/pci/ivtv/ivtv-ioctl.c
+++ b/drivers/media/pci/ivtv/ivtv-ioctl.c
@@ -1196,7 +1196,7 @@
 	return 0;
 }
 
-static int ivtv_s_tuner(struct file *file, void *fh, struct v4l2_tuner *vt)
+static int ivtv_s_tuner(struct file *file, void *fh, const struct v4l2_tuner *vt)
 {
 	struct ivtv_open_id *id = fh2id(fh);
 	struct ivtv *itv = id->itv;