Tegra: fix the NS DRAM address calculation logic
Tegra: fix the NS DRAM address calculation logic

This patch fixes the logic used to calculate the end of NS memory
aperture. The functions allows zero sized NS apertures as that is
a valid requirement for some use cases. e.g. VPR resize.

Change-Id: Ie966e0ea2f9c6888d21c38e734003704094b3720
Signed-off-by: Varun Wadekar <517ae08f01cae398dbba5bef5ba1750f384c6daf@nvidia.com>

lsigithub/arm-trusted-firmware_public,lsigithub/arm-trusted-firmware_public,achingupta/arm-trusted-firmware,achingupta/arm-trusted-firmware