media: pxa_camera: constify v4l2_clk_ops structure

This v4l2_clk_ops structure is only passed as the first argument of
v4l2_clk_register, which is const, so the v4l2_clk_ops structure can
also be const.

Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/platform/pxa_camera.c

@@ -2100,7 +2100,7 @@ static const struct v4l2_ioctl_ops pxa_camera_ioctl_ops = {
 	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
 };
 
-static struct v4l2_clk_ops pxa_camera_mclk_ops = {
+static const struct v4l2_clk_ops pxa_camera_mclk_ops = {
 };
 
 static const struct video_device pxa_camera_videodev_template = {