[media] v4l2: pass std by value to the write-only s_std ioctl

This ioctl is defined as IOW, so pass the argument by value instead of by
reference. I could have chosen to add const instead, but this is 1) easier
to handle in drivers and 2) consistent with the s_std subdev operation.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c b/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c
index 0f729c9..a7774e3 100644
--- a/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c
+++ b/drivers/media/usb/pvrusb2/pvrusb2-v4l2.c
@@ -196,13 +196,13 @@
 	return ret;
 }
 
-static int pvr2_s_std(struct file *file, void *priv, v4l2_std_id *std)
+static int pvr2_s_std(struct file *file, void *priv, v4l2_std_id std)
 {
 	struct pvr2_v4l2_fh *fh = file->private_data;
 	struct pvr2_hdw *hdw = fh->channel.mc_head->hdw;
 
 	return pvr2_ctrl_set_value(
-		pvr2_hdw_get_ctrl_by_id(hdw, PVR2_CID_STDCUR), *std);
+		pvr2_hdw_get_ctrl_by_id(hdw, PVR2_CID_STDCUR), std);
 }
 
 static int pvr2_querystd(struct file *file, void *priv, v4l2_std_id *std)