Add ESP8266 to RwReg definition

Author: siddacious

TouchScreen.h

@@ -12,7 +12,7 @@
 typedef volatile uint8_t RwReg;
 #elif defined(ARDUINO_STM32_FEATHER)
 typedef volatile uint32 RwReg;
-#elif defined(NRF52_SERIES) || defined(ESP32) || defined(ARDUINO_ARCH_STM32)
+#elif defined(NRF52_SERIES) || defined(ESP32) || defined(ESP8266) || defined(ARDUINO_ARCH_STM32)
 typedef volatile uint32_t RwReg;
 #else
 typedef volatile uint32_t RwReg;