send heartbeat if recieve no packets in 55Sec
send heartbeat if recieve no packets in 55Sec

Signed-off-by: Jeremy.L <6991411e709a2e7d8b306885b720b5c970f07f02@espressif.com>

Anwaarullah/esp8266_iot_platform,xunmengfeng/esp8266_iot_platform,iotcafe/esp8266_iot_platform,Anwaarullah/esp8266_iot_platform,iotcafe/esp8266_iot_platform,wurenditie/esp8266_iot_platform,wurenditie/esp8266_iot_platform,wurenditie/esp8266_iot_platform,xunmengfeng/esp8266_iot_platform,Anwaarullah/esp8266_iot_platform,xunmengfeng/esp8266_iot_platform,iotcafe/esp8266_iot_platform,wurenditie/esp8266_iot_platform,iotcafe/esp8266_iot_platform,Anwaarullah/esp8266_iot_platform,Anwaarullah/esp8266_iot_platform,xunmengfeng/esp8266_iot_platform,iotcafe/esp8266_iot_platform,wurenditie/esp8266_iot_platform,xunmengfeng/esp8266_iot_platform