ARC: [plat-axs10x]: prepare dts files for enabling PAE40 on axs103

Enable 64bit adressing, where it needed, to make possible
enabling PAE40 on axs103.

This patch doesn't affect on any functionality.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev-HKixBCOQz3hWk0Htik3J/w@public.gmane.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>