[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/em28xx/em28xx-video.c b/drivers/media/usb/em28xx/em28xx-video.c
index 3ef696d..96d84c2 100644
--- a/drivers/media/usb/em28xx/em28xx-video.c
+++ b/drivers/media/usb/em28xx/em28xx-video.c
@@ -996,23 +996,23 @@
 	return 0;
 }
 
-static int vidioc_s_std(struct file *file, void *priv, v4l2_std_id *norm)
+static int vidioc_s_std(struct file *file, void *priv, v4l2_std_id norm)
 {
 	struct em28xx_fh   *fh  = priv;
 	struct em28xx      *dev = fh->dev;
 	struct v4l2_format f;
 
-	if (*norm == dev->norm)
+	if (norm == dev->norm)
 		return 0;
 
 	if (dev->streaming_users > 0)
 		return -EBUSY;
 
-	dev->norm = *norm;
+	dev->norm = norm;
 
 	/* Adjusts width/height, if needed */
 	f.fmt.pix.width = 720;
-	f.fmt.pix.height = (*norm & V4L2_STD_525_60) ? 480 : 576;
+	f.fmt.pix.height = (norm & V4L2_STD_525_60) ? 480 : 576;
 	vidioc_try_fmt_vid_cap(file, priv, &f);
 
 	/* set new image size */