powerpc/celleb: Use for_each_compatible_node() macro

Use for_each_compatible_node() macro instead of open coding it.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/platforms/cell/celleb_scc_sio.c

@@ -42,14 +42,13 @@ static struct {
 static int __init txx9_serial_init(void)
 {
 	extern int early_serial_txx9_setup(struct uart_port *port);
-	struct device_node *node = NULL;
+	struct device_node *node;
 	int i;
 	struct uart_port req;
 	struct of_irq irq;
 	struct resource res;
 
-	while ((node = of_find_compatible_node(node,
-				"serial", "toshiba,sio-scc")) != NULL) {
+	for_each_compatible_node(node, "serial", "toshiba,sio-scc") {
 		for (i = 0; i < ARRAY_SIZE(txx9_scc_tab); i++) {
 			if (!(txx9_serial_bitmap & (1<<i)))
 				continue;