usb: gadget: uvc: constify vb2_ops structure

The vb2_ops structure can be const as it is only stored in the ops
field of a vb2_queue structure and this field is const.

Done with the help of Coccinelle.
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/gadget/function/uvc_queue.c

@@ -102,7 +102,7 @@ static void uvc_buffer_queue(struct vb2_buffer *vb)
 	spin_unlock_irqrestore(&queue->irqlock, flags);
 }
 
-static struct vb2_ops uvc_queue_qops = {
+static const struct vb2_ops uvc_queue_qops = {
 	.queue_setup = uvc_queue_setup,
 	.buf_prepare = uvc_buffer_prepare,
 	.buf_queue = uvc_buffer_queue,