ARM: socfpga: Add missing Denali NAND config options

The Denali SPL shim won't build without these options set,
set them accordingly to fix the build error and let the SPL
shim to work correctly.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>