MX5: efikamx: substitutes GPIO_NUMBER with IMX_GPIO_NR

The macro to get the gpio number id was renamed to
IMX_GPIO_NR as in kernel. Fix the wrong name in efika.

Signed-off-by: Stefano Babic <sbabic@denx.de>
CC: Matt Sealey <matt@genesi-usa.com>
Acked-by: Matt Sealey <matt@genesi-usa.com>