[coreboot] [PATCH] [v3] add pcengines alix.2c3

[Ward Vandewege]

Another product of the Denver summit. Thanks to the expert guidance of Ron,
Marc, Jordan and Stepan as well as the quality of the alix.1c v3 code, this
was probably the easiest port ever.

This patch is largely a copy-and-past from the alix.1c board, with some
tweaks (no superio, and the irqs are routed a bit differently).

One outstanding issue still - the usb ports fight over an interrupt with
eth2. Hopefully that will get fixed soon.

Tested on real hardware.

Thanks,
Ward.