sync with master

Author: d-a-v

libraries/esp8266/examples/UartDownload/UartDownload.ino

@@ -98,12 +98,6 @@ void proxyEspSync() {
 //
 ////////////////////////////////////////////////////////////////////////////////
 
-void preinit() {
- // (no C++ in function)
- // disable wifi
- ESP8266WiFiClass::preinitWiFiOff();
-}
-
 void setup() {
  // For `proxyEspSync()` to work, the Serial.begin() speed needs to be
  // 115200bps. This is the data rate used by esptool.py. It expects the Boot