test(fuzz): add FF-A fuzzing

Add necessary components for FF-A calls to be used in fuzzing framework
including bias tree, `run_ffa_fuzz` helper function, makefile additions,
and initial SMC description file with FF-A smc calls.

Can use ffa_smc_calls.txt to generate necessary header files.

Signed-off-by: Kathleen Capella <kathleen.capella@arm.com>
Change-Id: Ib19714342d31cacd818471686a7e4c8910fed5c3
9 files changed