Updated readme

README.md

@@ -34,6 +34,8 @@ RadioLib was originally created as a driver for [__RadioShield__](https://github
 * __Arduino AVR boards__ - tested on Uno, Mega and Leonardo
 * __ESP8266 boards__ - NodeMCU, Wemos D1, etc.
 * __ESP32 boards__ - tested on ESP-WROOM-32
+* __STM32 boards__ - tested on BluePill F103C6
+* __SAMD boards__ - Arduino Zero
 
 ### In development:
 * __SIM800C__ GSM module