of: use for_each_of_cpu_node iterator

Use the for_each_of_cpu_node iterator to iterate over cpu nodes. This
has the side effect of defaulting to iterating using "cpu" node names in
preference to the deprecated (for FDT) device_type == "cpu".

Cc: Frank Rowand <frowand.list@gmail.com>
Cc: devicetree@vger.kernel.org
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rob Herring <robh@kernel.org>

drivers/of/base.c

@@ -389,7 +389,7 @@ struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
 {
 	struct device_node *cpun;
 
-	for_each_node_by_type(cpun, "cpu") {
+	for_each_of_cpu_node(cpun) {
 		if (arch_find_n_match_cpu_physical_id(cpun, cpu, thread))
 			return cpun;
 	}