PCI: pnv_php: Add missing of_node_put()

The device node iterators perform an of_node_get() on each iteration, so a
jump out of the loop requires an of_node_put().

The semantic patch that fixes this problem is as follows
(http://coccinelle.lip6.fr):

// <smpl>
@@
expression root,e;
local idexpression child;
iterator name for_each_child_of_node;
@@

 for_each_child_of_node(root, child) {
   ... when != of_node_put(child)
       when != e = child
+  of_node_put(child);
?  break;
   ...
}
... when != child
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/hotplug/pnv_php.c

@@ -220,13 +220,17 @@ static int pnv_php_populate_changeset(struct of_changeset *ocs,
 
 	for_each_child_of_node(dn, child) {
 		ret = of_changeset_attach_node(ocs, child);
-		if (ret)
+		if (ret) {
+			of_node_put(child);
 			break;
+		}
 
 		ret = pnv_php_populate_changeset(ocs, child);
-		if (ret)
+		if (ret) {
+			of_node_put(child);
 			break;
 		}
+	}
 
 	return ret;
 }