Examples update, add a note for configTime() that only one ntp server is supported by lwip

Signed-off-by: Emil Muratov <gpm@hotplug.ru>

Author: vortigont

Diff for: cores/esp32/esp32-hal-time.c

@@ -44,6 +44,8 @@ static void setTimeZone(long offset, int daylight)
 /*
  * configTime
  * Source: https://github.com/esp8266/Arduino/blob/master/cores/esp8266/time.c
+ * Note: Bundled Arduino lwip supports only ONE ntp server, 2nd and 3rd options are silently ignored
+ *       see CONFIG_LWIP_DHCP_MAX_NTP_SERVERS define in ./tools/sdk/esp32/sdkconfig
  * */
 void configTime(long gmtOffset_sec, int daylightOffset_sec, const char* server1, const char* server2, const char* server3)
 {
@@ -63,6 +65,8 @@ void configTime(long gmtOffset_sec, int daylightOffset_sec, const char* server1,
 /*
  * configTzTime
  * sntp setup using TZ environment variable
+ * Note: Bundled Arduino lwip supports only ONE ntp server, 2nd and 3rd options are silently ignored
+ *       see CONFIG_LWIP_DHCP_MAX_NTP_SERVERS define in ./tools/sdk/esp32/sdkconfig
  * */
 void configTzTime(const char* tz, const char* server1, const char* server2, const char* server3)
 {

Diff for: libraries/FFat/examples/FFat_time/FFat_time.ino

@@ -148,6 +148,10 @@ void setup(){
     Serial.println("IP address: ");
     Serial.println(WiFi.localIP());
     Serial.println("Contacting Time Server");
+    /*
+        Note: Bundled Arduino lwip supports only ONE ntp server, 2nd and 3rd options are silently ignored
+        see CONFIG_LWIP_DHCP_MAX_NTP_SERVERS define in ./tools/sdk/esp32/sdkconfig
+     */
 	configTime(3600*timezone, daysavetime*3600, "time.nist.gov", "0.pool.ntp.org", "1.pool.ntp.org");
 	struct tm tmstruct ;
     delay(2000);

Diff for: libraries/HTTPUpdate/examples/httpUpdateSecure/httpUpdateSecure.ino

@@ -17,6 +17,10 @@ WiFiMulti WiFiMulti;
 
 // Set time via NTP, as required for x.509 validation
 void setClock() {
+  /*
+    Note: Bundled Arduino lwip supports only ONE ntp server, 2nd and 3rd options are silently ignored
+    see CONFIG_LWIP_DHCP_MAX_NTP_SERVERS define in ./tools/sdk/esp32/sdkconfig
+  */
   configTime(0, 0, "pool.ntp.org", "time.nist.gov");  // UTC
 
   Serial.print(F("Waiting for NTP time sync: "));

Diff for: libraries/LITTLEFS/examples/LITTLEFS_time/LITTLEFS_time.ino

@@ -160,6 +160,10 @@ void setup(){
     Serial.println("IP address: ");
     Serial.println(WiFi.localIP());
     Serial.println("Contacting Time Server");
+    /*
+        Note: Bundled Arduino lwip supports only ONE ntp server, 2nd and 3rd options are silently ignored
+        see CONFIG_LWIP_DHCP_MAX_NTP_SERVERS define in ./tools/sdk/esp32/sdkconfig
+     */
 	configTime(3600*timezone, daysavetime*3600, "time.nist.gov", "0.pool.ntp.org", "1.pool.ntp.org");
 	struct tm tmstruct ;
     delay(2000);

Diff for: libraries/SD/examples/SD_time/SD_time.ino

@@ -164,6 +164,10 @@ void setup(){
     Serial.println("IP address: ");
     Serial.println(WiFi.localIP());
     Serial.println("Contacting Time Server");
+    /*
+        Note: Bundled Arduino lwip supports only ONE ntp server, 2nd and 3rd options are silently ignored
+        see CONFIG_LWIP_DHCP_MAX_NTP_SERVERS define in ./tools/sdk/esp32/sdkconfig
+     */
 	configTime(3600*timezone, daysavetime*3600, "time.nist.gov", "0.pool.ntp.org", "1.pool.ntp.org");
 	struct tm tmstruct ;
     delay(2000);

Diff for: libraries/SD_MMC/examples/SDMMC_time/SDMMC_time.ino

@@ -164,6 +164,10 @@ void setup(){
     Serial.println("IP address: ");
     Serial.println(WiFi.localIP());
     Serial.println("Contacting Time Server");
+    /*
+        Note: Bundled Arduino lwip supports only ONE ntp server, 2nd and 3rd options are silently ignored
+        see CONFIG_LWIP_DHCP_MAX_NTP_SERVERS define in ./tools/sdk/esp32/sdkconfig
+     */
 	configTime(3600*timezone, daysavetime*3600, "time.nist.gov", "0.pool.ntp.org", "1.pool.ntp.org");
 	struct tm tmstruct ;
     delay(2000);

Diff for: libraries/SPIFFS/examples/SPIFFS_time/SPIFFS_time.ino

@@ -148,6 +148,10 @@ void setup(){
     Serial.println("IP address: ");
     Serial.println(WiFi.localIP());
     Serial.println("Contacting Time Server");
+    /*
+        Note: Bundled Arduino lwip supports only ONE ntp server, 2nd and 3rd options are silently ignored
+        see CONFIG_LWIP_DHCP_MAX_NTP_SERVERS define in ./tools/sdk/esp32/sdkconfig
+     */
 	configTime(3600*timezone, daysavetime*3600, "time.nist.gov", "0.pool.ntp.org", "1.pool.ntp.org");
 	struct tm tmstruct ;
     delay(2000);