plat/sgi: allow usage of secure partions on rdn2 platform

Add the secure partition mmap table and the secure partition boot
information to support secure partitions on RD-N2 platform. In addition
to this, add the required memory region mapping for accessing the
SoC peripherals from the secure partition.

Signed-off-by: Omkar Anand Kulkarni <omkar.kulkarni@arm.com>
Change-Id: I2c75760d6c8c3da3ff4885599be420e924aeaf3c
3 files changed