Platform: Add fault injection mitigation to AN521

Create a reference implementation to show how can the configuration
of memory isolation hardware protected against physical attacks.

Signed-off-by: Tamas Ban <tamas.ban@arm.com>
Co-authorized-by: David Hu <david.hu@arm.com>
Change-Id: I470d6b495182530b84f9fc3a164e8a880775a250
8 files changed