mtd: physmap_of: assign parent for the concatenated MTD

If there is more than one map region for this device, then the
concatenated MTD will not have a parent device assigned to it -- only
the sub-devices (which are not actually registered with the framework)
will have their parents assigned. Let's assign the concatenated device
correctly.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>

drivers/mtd/maps/physmap_of.c

@@ -309,6 +309,7 @@ static int of_flash_probe(struct platform_device *dev)
 	if (err)
 		goto err_out;
 
+	info->cmtd->dev.parent = &dev->dev;
 	mtd_set_of_node(info->cmtd, dp);
 	part_probe_types = of_get_probes(dp);
 	if (!part_probe_types) {