[media] v4l2: make vidioc_s_crop const

Write-only ioctls should have a const argument in the ioctl op.
Do this conversion for vidioc_s_crop.
Adding const for write-only ioctls was decided during the 2012 Media Workshop.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.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 d5cbb61..ed6dcc7 100644
--- a/drivers/media/pci/ivtv/ivtv-ioctl.c
+++ b/drivers/media/pci/ivtv/ivtv-ioctl.c
@@ -874,7 +874,7 @@
 	return 0;
 }
 
-static int ivtv_s_crop(struct file *file, void *fh, struct v4l2_crop *crop)
+static int ivtv_s_crop(struct file *file, void *fh, const struct v4l2_crop *crop)
 {
 	struct ivtv_open_id *id = fh2id(fh);
 	struct ivtv *itv = id->itv;