ESP8266_NONOS_SDK_V2.0.0使用libssl说明：
启用certificate auth需要调用configTime接口启用sntp，否则会由于日期出现证书校验失败，且不支持证书有效期超过2038年12月31日。
/**
* @brief Config the time info of the SNTP server addr.
*
* @param timezone--Settings do not take effect until SNTP time is updated, Allowed values are in the range [-11, 13].
* daylightOffset--Settings do not take effect until SNTP time is updated, Allowed values are in the range [0, 24].
* server1--SNTP Server1.
* server2--SNTP Server2.
* server3--SNTP Server3.
* enable--enable or disable RTC,only support false now.
* @return true or false
*/
bool configTime(int timezone, int daylightOffset, char* server1, char* server2, char* server3, bool enable);
eg:
configTime(8, 0, "cn.ntp.org.cn", "ntp.sjtu.edu.cn", "us.pool.ntp.org", false);
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ESP8266_NONOS_SDK_V2.0.0 using libssl：
For ESP8266_NONOS_SDK_V2.0.0 using libssl, the following conditions are needed:
if we are using certificate auth, we need to use the configTime API to provide SNTP, otherwise the certification will expire. We also do not support expire date > 2038.
/**
* @brief Config the time info of the SNTP server addr.
*
* @param timezone--Settings do not take effect until SNTP time is updated, Allowed values are in the range [-11, 13].
* daylightOffset--Settings do not take effect until SNTP time is updated, Allowed values are in the range [0, 24].
* server1--SNTP Server1.
* server2--SNTP Server2.
* server3--SNTP Server3.
* enable--enable or disable RTC,only support false now.
* @return true or false
*/
bool configTime(int timezone, int daylightOffset, char* server1, char* server2, char* server3, bool enable);
eg:
configTime(8, 0, "cn.ntp.org.cn", "ntp.sjtu.edu.cn", "us.pool.ntp.org", false);