Initial import of Bitmine.ch A1 SPI driver
This initial driver was designed around an FPGA based
emulator board which provides 2 chained chips with 4
hashing engines each, running at 10% of the A1's
nominal speed.
Driver has been tested on RasPi.
Signed-off-by: Zefir Kurtisi <zefir.kurtisi@gmail.com>
