The Tegra memctrl driver sets up the TZDRAM fence during boot and
system suspend exit. This patch provides individual platforms with
handlers to perform platform specific steps, e.g. enable encryption,
save base/size to secure scratch registers.

Change-Id: Ifaa2e0eac20b50f77ec734256544c36dd511bd63
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>