[media] vb2: replace void *alloc_ctxs by struct device *alloc_devs

Make this a proper typed array. Drop the old allocate context code since
that is no longer used.

Note that the memops functions now get a struct device pointer instead of
the struct device ** that was there initially (actually a void pointer to
a struct containing only a struct device pointer).

This code is now a lot cleaner.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Sakari Ailus <sakari.ailus@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
diff --git a/drivers/input/touchscreen/sur40.c b/drivers/input/touchscreen/sur40.c
index cc4bd3e..f124f3a 100644
--- a/drivers/input/touchscreen/sur40.c
+++ b/drivers/input/touchscreen/sur40.c
@@ -645,7 +645,7 @@
  */
 static int sur40_queue_setup(struct vb2_queue *q,
 		       unsigned int *nbuffers, unsigned int *nplanes,
-		       unsigned int sizes[], void *alloc_ctxs[])
+		       unsigned int sizes[], struct device *alloc_devs[])
 {
 	if (q->num_buffers + *nbuffers < 3)
 		*nbuffers = 3 - q->num_buffers;