ARM: tegra: use 2 address cells for Tegra124 DT

Tegra124 can support 4GB of RAM. With that much RAM (plus some memory-
mapped IO peripherals), more than 32-bits of physical address space is
required. Hence, convert all Tegra124 DTs to use 2 DT cells for address
space.

(I think this was suggested by Olof Johansson, but I'm not 100% sure)

Signed-off-by: Stephen Warren <swarren@nvidia.com>