Set OTA name as Gateway_Short_Name + MAC if using mac as gateway name. (#1023)

* Set OTA name as Gateway_Short_Name + MAC if using mac as gateway name.

This will set the OTA name of the gateway to the *Gateway_Short_Name*_*MAC* when USE_MAC_AS_GATEWAY_NAME is defined in the config.

* Log OTA hostname when using MAC as gateway name.

main/main.ino

@@ -168,7 +168,10 @@ char mqtt_topic[mqtt_topic_max_size] = Base_Topic;
 char gateway_name[parameters_size * 2] = Gateway_Name;
 #ifdef USE_MAC_AS_GATEWAY_NAME
 #  undef WifiManager_ssid
-char WifiManager_ssid[20];
+#  undef ota_hostname
+#  define MAC_NAME_MAX_LEN 30
+char WifiManager_ssid[MAC_NAME_MAX_LEN];
+char ota_hostname[MAC_NAME_MAX_LEN];
 #endif
 bool connectedOnce = false; //indicate if we have been connected once to MQTT
 int failure_number_ntwk = 0; // number of failure connecting to network
@@ -595,7 +598,9 @@ void setup() {
   String s = WiFi.macAddress();
   sprintf(gateway_name, "%.2s%.2s%.2s%.2s%.2s%.2s",
           s.c_str(), s.c_str() + 3, s.c_str() + 6, s.c_str() + 9, s.c_str() + 12, s.c_str() + 15);
-  sprintf(WifiManager_ssid, "%s_%s", Gateway_Short_Name, gateway_name);
+  snprintf(WifiManager_ssid, MAC_NAME_MAX_LEN, "%s_%s", Gateway_Short_Name, gateway_name);
+  strcpy(ota_hostname, WifiManager_ssid);
+  Log.notice(F("OTA Hostname: %s.local" CR), ota_hostname);
 #  endif
 
 #  ifdef ESP32_ETHERNET