ts72xx NAND driver

The TS-72xx is a series of embedded single board computers from
Technologic Systems based on the Cirrus ep93xx (arm920t based) CPU.

The TS-7200 uses NOR flash, while all the other models in the series
(TS-7250, TS-7260) use NAND flash -- included is a driver for the NAND
flash on those boards.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>