feat(spmd): add FFA_MSG_SEND_DIR_REQ2

Add handling for FF-A 1.2 FFA_MSG_SEND_DIR_REQ2 interface.
Handler validates security states of sender/receiver pairs
and forwards the call to other world if necessary.

Signed-off-by: Kathleen Capella <kathleen.capella@arm.com>
Change-Id: I02a60362d8d9a50fcc0b6a84753cba274ba5eb1b
2 files changed