[POWERPC] Add for_each_compatible_node()

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

include/asm-powerpc/prom.h

@@ -124,6 +124,9 @@ extern struct device_node *of_find_node_by_type(struct device_node *from,
 	     dn = of_find_node_by_type(dn, type))
 extern struct device_node *of_find_compatible_node(struct device_node *from,
 	const char *type, const char *compat);
+#define for_each_compatible_node(dn, type, compatible) \
+	for (dn = of_find_compatible_node(NULL, type, compatible); dn; \
+	     dn = of_find_compatible_node(dn, type, compatible))
 extern struct device_node *of_find_node_by_path(const char *path);
 extern struct device_node *of_find_node_by_phandle(phandle handle);
 extern struct device_node *of_find_all_nodes(struct device_node *prev);