v1.5.3 using built-in ESP32 MAC Address

#### Releases v1.5.3

1. Using `built-in ESP32 MAC Address`
2. Increase default `SPI_CLOCK_MHZ` clock to 20MHz from 8MHz

README.md

@@ -126,7 +126,7 @@ This [**WebServer_ESP32_ENC** library](https://github.com/khoih-prog/WebServer_E
 ## Prerequisites
 
  1. [`Arduino IDE 1.8.19+` for Arduino](https://github.com/arduino/Arduino). [![GitHub release](https://img.shields.io/github/release/arduino/Arduino.svg)](https://github.com/arduino/Arduino/releases/latest)
- 2. [`ESP32 Core 2.0.5+`](https://github.com/espressif/arduino-esp32) for ESP32-based ESP32_DEV with ENC28J60 boards using release `v1.3.0+`. [![Latest release](https://img.shields.io/github/release/espressif/arduino-esp32.svg)](https://github.com/espressif/arduino-esp32/releases/latest/)
+ 2. [`ESP32 Core 2.0.6+`](https://github.com/espressif/arduino-esp32) for ESP32-based ESP32_DEV with ENC28J60 boards using release `v1.3.0+`. [![Latest release](https://img.shields.io/github/release/espressif/arduino-esp32.svg)](https://github.com/espressif/arduino-esp32/releases/latest/)
 
 
 ---