update mqtt client

update mqtt client

components/connectivity/mqttclient/network/network.h

@@ -2,7 +2,7 @@
  * @Author: jiejie
  * @Github: https://github.com/jiejieTop
  * @Date: 2019-12-09 21:31:02
- * @LastEditTime: 2020-05-21 01:09:29
+ * @LastEditTime: 2020-10-17 14:14:41
  * @Description: the code belongs to jiejie, please keep the author information and source code according to the license.
  */
 #ifndef _NETWORK_H_
@@ -10,6 +10,10 @@
 
 #include "mqtt_defconfig.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #define     NETWORK_CHANNEL_TCP     0
 #define     NETWORK_CHANNEL_TLS     1
 
@@ -36,4 +40,8 @@ int network_connect(network_t* n);
 void network_disconnect(network_t *n);
 void network_release(network_t* n);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif