uboot-phytec

i.MX31 PDK: Enable generic board for i.MX31 PDK

Enable CONFIG_SYS_GENERIC_BOARD for the i.MX31 PDK board.

Tested on actual hardware.

Signed-off-by: Magnus Lilja <lilja.magnus@gmail.com>
Acked-by: Fabio Estevam <fabio.estevam@freescale.com>