SPI chip select/slave select not working

[kris-toth]

The bug
The slave select doesn't pull down during transfer.

Description

1. Using pocketbeagle, with robotcontrollib 1.0.5, and an SPI device (RFM26W but doesn't matter)
2. Running the 'rc_spi_loopback.c' example
3. using 'rc_spi_init_auto_slave(BUS, SLAVE, BUS_MODE, SPI_SPEED)'
4. Verified with oscilloscope, that the CS line doesnt move during the program. CS goes high at program start and goes low on exit.

Temporary fix
Temporary fix with 'rc_spi_init_manual_slave(BUS, SLAVE, BUS_MODE, SPI_SPEED, chip, pin)' and manual manipulation of CS with rc_spi_manual_select(BUS, SLAVE, 0) / rc_spi_manual_select(BUS, SLAVE, 1) before/after every spi event.
This way cant use hardware CS.