ARM: OMAP1: ams-delta: Provide GPIO lookup table for NAND data port

Data port used by Amstrad Delta NAND driver is actually an OMAP MPUIO
device, already under control of gpio-omap driver.  The NAND driver
gets access to the port by ioremapping it and performs read/write
operations.  That is done without any proteciton from other users
legally manipulating the port pins over GPIO API.

The plan is to convert the driver to access the port over GPIO consumer
API.  Before that is implemented, the driver can already obtain
exclusive access to the port by requesting an array of its GPIO
descriptors.

Add respective entries to the NAND GPIO lookup table.

Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>