mtd: nand: omap: free region as per resource size
mtd: nand: omap: free region as per resource size

memory as is now obtained via resource, upon freeing use
resource size. This also helps get rid of one macro.

Signed-off-by: Afzal Mohammed <e2d4496628a80d9d19704e42be4aec0b278f228a@ti.com>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs