[component][sal]add netgetdev api

components/net/netdev/include/netdev.h

@@ -155,6 +155,9 @@ struct netdev *netdev_get_by_name(const char *name);
 struct netdev *netdev_get_by_family(int family);
 int netdev_family_get(struct netdev *netdev);
 #endif /* RT_USING_SAL */
+#if defined(SAL_USING_AF_NETLINK)
+int netdev_getnetdev(struct msg_buf *msg, int (*cb)(struct msg_buf *m_buf, struct netdev *nd, int nd_num, int index, int ipvx));
+#endif
 
 /* Set default network interface device in list */
 void netdev_set_default(struct netdev *netdev);