a sample driver for the TI TMP121 temperature sensor. This has been
moderately tested on Au1550, and it is not enabled in sys/conf (yet). So
the change is harmless at worst, and useful at best.
Alchemy Au1550 bus driver forthcoming, along with a driver for SPI flash
devices, such as found on the Meraki Mini
This development was partially funded by the Champaign-Urbana Community
Wireless Network Project.
Note that there are some MD-specific SPI drivers that could probably be
made MI under this new framework.