test(ff-a): clear memory for mem share between NWd and SWd

Add test to validate that memory is cleared on memory sharing operations
between the SWd and NWd.

Signed-off-by: J-Alves <joao.alves@arm.com>
Change-Id: Ia1ac0f2a542b7498ac2ef6910d3af4bdb2f7755b
2 files changed