Added NRF52Board.h and NRF52Board.cpp Modified NRF52 variants to extend from NRF52Board to share common feature
Add the necessary code to properly power-off the Xiao + Wio companions. This way we can achieve around 15 microamps of power consumption in the off state. Signed-off-by: Frieder Schrempf <frieder@fris.de>
move variant specific code out of src/helpers redefine RXEN for alternate radio pinout
