Adding tests for Realm payload

This testing patch has the following test scenarios for realm payload:

1. Query the RMI Version on a single CPU.
2. Multi CPU version query.
3. Test to delegate and undelegate a buffer using RMI Delegate and
Undelegate commands.

Change-Id: I76a1274cb395860fd9fb2b9f3db44eae81ca65c6
Signed-off-by: Mark Dykes <mark.dykes@arm.com>
9 files changed