powerpc: Use of for_each_node_by_name() instead of open-coding it

Instead of manually coding the loop with of_find_node_by_name(), let's
switch to the standard macro for iterating over nodes with given name.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
[mpe: Fix build failures due to typo in mpc832x_mds.c]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/cell/spider-pic.c

@@ -343,8 +343,7 @@ void __init spider_init_IRQ(void)
 	 * device-tree is bogus anyway) so all we can do is pray or maybe test
 	 * the address and deduce the node-id
 	 */
-	for (dn = NULL;
-	     (dn = of_find_node_by_name(dn, "interrupt-controller"));) {
+	for_each_node_by_name(dn, "interrupt-controller") {
 		if (of_device_is_compatible(dn, "CBEA,platform-spider-pic")) {
 			if (of_address_to_resource(dn, 0, &r)) {
 				printk(KERN_WARNING "spider-pic: Failed\n");