[PATCH][RESEND] sama5d3x: fix AT91_SMC_CS offset stride

[Matteo Fortini]

As stated in section 29.19.32 of SAMA5D3 Series datasheet, to move
from CS(n) to CS(n+1) the stride is 0x14 and not 0x10.

For this reason, I was unable to use the NAND memory on my board (CS
configuration was not applied and the timings were wrong).

This patch fixes the problem.

Matteo