feat(spmc): add helper to obtain a partitions FF-A version

Add a helper function to obtain the FF-A version of a calling
partition. This is used to ensure that the SPMC maintains
backwards compatibility if the partition implements a lower
minor version for the same major version than the SPMC.

Signed-off-by: Marc Bonnici <marc.bonnici@arm.com>
Change-Id: I5b364a1e510a999bb0c4cacae28f23f8a42a1e3e
1 file changed