Add line for Atmega4808

[andonoc]

Hello, sorry but i cant use GIT properly and i don't know how to make a pull request. For using a ATMEGA4808 i changed line 18 in util/OneWire_direct_gpio.h to

if defined(AVR_ATmega4809) || (AVR_ATmega4808)

after this change the library works for me.

[sameSEA]

Thank this, it saved me time! With Platformio and MegaCoreX that line 18 should be: #if defined(__AVR_ATmega4809__) || defined(__AVR_ATmega4808__)

or just

if defined(MEGACOREX)