[fix] format

components/net/lwip-2.1.2/src/netif/ethernetif.c

 /*
  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
- * COPYRIGHT (C) 2006-2018, RT-Thread Development Team
+ * COPYRIGHT (C) 2006-2021, RT-Thread Development Team
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without modification,

components/net/netdev/src/netdev.c

@@ -1154,7 +1154,7 @@ int netdev_ping(int argc, char **argv)
 {
     if (argc == 1)
     {
-        rt_kprintf("Please input: ping <host address>\n");
+        rt_kprintf("Please input: ping [netdev name] <host address>\n");
     }
     else if (argc == 2)
     {