board/ls2085a: Update env_addr after NOR flash relocation

LS2085a has 2 regions in system memory map. Region1 is default map from
where system boots. Once u-boot is moved to DDR, IFC is re-mapped to
Region2.

So, update gd->env_addr to reflect correct address.

Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>