Update netdev.c

根据family查找netdev时，优先查找family匹配并且已经联网的网卡
再查找family匹配但是未联网的网卡

components/net/netdev/src/netdev.c

@@ -269,7 +269,7 @@ struct netdev *netdev_get_by_family(int family)
     {
         netdev = rt_slist_entry(node, struct netdev, list);
         pf = (struct sal_proto_family *) netdev->sal_user_data;
-        if (pf && pf->skt_ops && pf->family == family && netdev_is_up(netdev))
+        if (pf && pf->skt_ops && pf->family == family && netdev_is_up(netdev) && netdev_is_link_up(netdev))
         {
             rt_hw_interrupt_enable(level);
             return netdev;