media: atmel-isc: constify vb2_ops structure

Check for vb2_ops structures that are only stored in the ops field of a
vb2_queue structure. That field is declared const, so vb2_ops structures
that have this property can be declared as const also.

This issue was detected using Coccinelle and the following semantic patch:

@r disable optional_qualifier@
identifier i;
position p;
@@
static struct vb2_ops i@p = { ... };

@ok@
identifier r.i;
struct vb2_queue e;
position p;
@@
e.ops = &i@p;

@bad@
position p != {r.p,ok.p};
identifier r.i;
struct vb2_ops e;
@@
e@i@p

@depends on !bad disable optional_qualifier@
identifier r.i;
@@
static
+const
struct vb2_ops i = { ... };

Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/platform/atmel/atmel-isc.c

@@ -873,7 +873,7 @@ static void isc_buffer_queue(struct vb2_buffer *vb)
 	spin_unlock_irqrestore(&isc->dma_queue_lock, flags);
 }
 
-static struct vb2_ops isc_vb2_ops = {
+static const struct vb2_ops isc_vb2_ops = {
 	.queue_setup		= isc_queue_setup,
 	.wait_prepare		= vb2_ops_wait_prepare,
 	.wait_finish		= vb2_ops_wait_finish,