media: software_node: unregister software_nodes in reverse order

To maintain consistency with software_node_unregister_nodes(), reverse
the order in which the software_node_unregister_node_group() function
unregisters nodes.
Reported-by: Nkernel test robot <lkp@intel.com>
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Suggested-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NDaniel Scally <djrscally@gmail.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/base/swnode.c

@@ -779,16 +779,23 @@ EXPORT_SYMBOL_GPL(software_node_register_node_group);
  * software_node_unregister_node_group - Unregister a group of software nodes
  * @node_group: NULL terminated array of software node pointers to be unregistered
  *
- * Unregister multiple software nodes at once.
+ * Unregister multiple software nodes at once. The array will be unwound in
+ * reverse order (i.e. last entry first) and thus if any members of the array are
+ * children of another member then the children must appear later in the list such
+ * that they are unregistered first.
  */
-void software_node_unregister_node_group(const struct software_node **node_group)
+void software_node_unregister_node_group(
+		const struct software_node **node_group)
 {
-	unsigned int i;
+	unsigned int i = 0;
 
 	if (!node_group)
 		return;
 
-	for (i = 0; node_group[i]; i++)
+	while (node_group[i])
+		i++;
+
+	while (i--)
 		software_node_unregister(node_group[i]);
 }
 EXPORT_SYMBOL_GPL(software_node_unregister_node_group);