[ospfd] Minor enhancements to recent self-host-routes suppression patch

	* ospf_spf.c: (ospf_spf_process_stubs) Track whether
	  parent router vertex is the root, so that the host-route
	  suppression logic need only be activated for such vertices.
	  Move the actual logic to ospf_intra_add_stub.
	* ospf_route.c: (ospf_intra_add_stub) Main test of link moved
	  here, notionally more appropriate.
diff --git a/ospfd/ospf_route.h b/ospfd/ospf_route.h
index 351e014..0d37436 100644
--- a/ospfd/ospf_route.h
+++ b/ospfd/ospf_route.h
@@ -140,7 +140,8 @@
 
 extern void ospf_intra_add_stub (struct route_table *,
 				 struct router_lsa_link *, struct vertex *,
-				 struct ospf_area *);
+				 struct ospf_area *,
+				 int parent_is_root);
 
 extern int ospf_route_cmp (struct ospf *, struct ospf_route *,
 			   struct ospf_route *);