loci: convert internal users away from inheritance union

This mostly affects list accessors.
diff --git a/c_gen/templates/README b/c_gen/templates/README
index 71c4a48..44eedab 100644
--- a/c_gen/templates/README
+++ b/c_gen/templates/README
@@ -60,7 +60,7 @@
     for (i = 1; i <= 4; i++) {
         of_action_output_t action;
         of_action_output_init(&action, flow_add->version, -1, 1);
-        of_list_action_append_bind(&actions, (of_action_t *)&action);
+        of_list_action_append_bind(&actions, &action);
         of_action_output_port_set(&action, i);
     }