This patch moves the TZDRAM base address to SCRATCH55_LO due
to security concerns. The HI and LO address bits are packed
into SCRATCH55_LO for the warmboot firmware to restore.
SCRATCH54_HI is still being used for backward compatibility,
but would be removed eventually.

The scratch registers are populated as:
* RSV55_0 = CFG1[12:0] | CFG0[31:20]
* RSV55_1 = CFG3[1:0]
* RSV54_1 = CFG1[12:0]

Change-Id: Idc20d165d8117488010fcc8dfd946f7ad475da58
Signed-off-by: Harvey Hsieh <hhsieh@nvidia.com>