Adds support for the MSP430X's 12-bit ADC peripheral, as well as
reasonably complete testing of same.
Also includes fixes for several bugs and cleanup of the DMA peripheral,
which used ch calls rather than osal calls and was unclear about what
contexts its methods could be called from.
A DMA-driven SPI driver and fairly comprehensive test code for SPI
on the MSP430X port. Required some cleanup to the DMA and Serial
drivers as well. Includes some reformatting to be more in line with
ChibiOS coding standards.
Fabio Utzig
Fabien Poussin
Andrew Wygle