ARM: OMAP1: ams-delta: Drop obsolete NAND resources

Amstrad Delta NAND driver now uses GPIO API for data I/O so there is no
need to assign memory I/O resource to the device any longer.  Drop it.

Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>