Add cubietruck fex file (with extracted dram_para)

The cubietruck is a new A20 based board by cubietech. It's similar to
the cubieboard, but has a nicer form-factor and more external
connectors, 2 GiB of Ram, Gigabit PHY and BT/WIFI module on board.

Signed-off-by: Oliver Schinagl <oliver@schinagl.nl>