Add a convenience macro for iterating over graph endpoints. Iterating over
graph endpoints using fwnode_graph_get_next_endpoint() is a recurring
pattern, and this macro allows calling that function in a slightly more
convenient way. For instance,
	for (child = NULL;
	     (child = fwnode_graph_get_next_endpoint(fwnode, child)); )
becomes
	fwnode_graph_for_each_endpoint(fwnode, child)
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
 fwnode_graph_get_remote_node(const struct fwnode_handle *fwnode, u32 port,
                             u32 endpoint);
 
+#define fwnode_graph_for_each_endpoint(fwnode, child)                  \
+       for (child = NULL;                                              \
+            (child = fwnode_graph_get_next_endpoint(fwnode, child)); )
+
 int fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
                                struct fwnode_endpoint *endpoint);