Added WiFi.disconnect to ESPNow examples. Fixes https://github.com/espressif/arduino-esp32/issues/1425 (#1511)

libraries/ESP32/examples/ESPNow/Basic/Slave/Slave.ino

@@ -36,6 +36,7 @@
 
 // Init ESP Now with fallback
 void InitESPNow() {
+  WiFi.disconnect();
   if (esp_now_init() == ESP_OK) {
     Serial.println("ESPNow Init Success");
   }
@@ -87,4 +88,4 @@ void OnDataRecv(const uint8_t *mac_addr, const uint8_t *data, int data_len) {
 
 void loop() {
   // Chill
-}
+}