ESP8266WiFi: initialise new STA configuration fields

Author: igrr

libraries/ESP8266WiFi/src/ESP8266WiFiSTA.cpp

@@ -126,6 +126,11 @@ wl_status_t ESP8266WiFiSTAClass::begin(const char* ssid, const char *passphrase,
         *conf.password = 0;
     }
 
+    conf.threshold.rssi = -127;
+
+    // TODO(#909): set authmode to AUTH_WPA_PSK if passphrase is provided
+    conf.threshold.authmode = AUTH_OPEN;
+
     if(bssid) {
         conf.bssid_set = 1;
         memcpy((void *) &conf.bssid[0], (void *) bssid, 6);