iBUSTelemetry.h compile error for STM32

@Tordens It's my library which I wrote a few years ago for my own hexa drone. I totally forgot about it! This lib was written strictly for AVR (in my case Arduino Pro Micro) and needs to be adjusted for ESP32. If you have any questions, write me an email -> a.slomian@outlook.com.
Best regards, guys!
Adam