Not accepting default routes retracted

Causes to reinstall the uninstalled default route, which does create unreachable hosts when using IPv6 source routing with multiple sources

Author: Dando-Real-ITA

route.c

@@ -731,6 +731,8 @@ route_acceptable(struct babel_route *route, int feasible,
         return 0;
     if(exclude && route->neigh == exclude)
         return 0;
+    if(route->refmetric == INFINITY && is_default(route->src->prefix, route->src->plen))
+        return 0;
     return 1;
 }