feat(ls64): add a test for 64byte loads/stores instructions

This patch adds a test to verify the 64 byte load and store
instructions introduced by FEAT_LS64.
The test primarily executes instructions:
1. LD64B
2. ST64B
and ensures that the NS-EL2 has no dependency on EL3 while
running them.

Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
Signed-off-by: Juan Pablo Conde <juanpablo.conde@arm.com>
Change-Id: I7a4ca0ee4a2c18bf0de030c72e35eb218bc6364c
9 files changed