Tegra194 supports upto 64GB of DRAM, whereas the previous SoCs support
upto 32GB DRAM. This patch moves the common DRAM base/end macros to
individual Tegra SoC headers to fix this anomaly.

Change-Id: I1a9f386b67c2311baab289e726d95cef6954071b
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>