Test: test framework and test suites

 -- Test framework
 -- Test secure service
 -- TFM Core secure/non-secure test suites
 -- SST secure/non-secure test suites

Change-Id: I5868d9a65a740b984748d975a3a5bd486cbfafc4
Signed-off-by: Abhishek Pandit <abhishek.pandit@arm.com>
Co-Authored-By: Mate Toth-pal <mate.toth-pal@arm.com>
Co-Authored-By: Antonio de Angelis <antonio.deangelis@arm.com>
Co-Authored-By: Miklos Balint <miklos.balint@arm.com>
Co-Authored-By: Jamie Fox <jamie.fox@arm.com>
Co-Authored-By: Ashutosh Singh <ashutosh.singh@arm.com>