Progress with NuttX

[l--putt]

Hi list,

with a bit of help from Harald, I finally managed to push my commits.
Hence, we have:

- platform support for Calypso (timers, irq, ...)
- char device driver for keypad (/dev/keypad)
- some hacks reusing old drivers for SPI/poweroff and sercomm

The console currently outputs in osmocon while you have to write to the
loader interface with a python script. Flushing is kind of a problem
too. Haven't checked how to fix those two, so any volunteers?


Bye,
Stefan