feat(rme): add GPT Library

This patch introduces the Granule Protection Table (GPT)
library code. This implementation will be updated later to
be more flexible, as the current implementation is very rigid.

Signed-off-by: Zelalem Aweke <zelalem.aweke@arm.com>
Change-Id: I3af824a28c6e9a5d36459c0c51d2d9bebfba1505
7 files changed