feat(ras): test to verify SErros synchronized at EL3 boundry

Tests to verify SErrors which gets triggered as part of error
synchronization at EL3 entry.
In FFH mode, EL3 does nested exception handling while in KFH it
reflectes it back to TF-A Tests.

Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: I5a980ed49ee47ea2f0d5685ba8378d48393ad157
6 files changed