feat(ff-a): update FF-A version to v1.2

Bump the required FF-A version in framework and manifests to v1.2 as
upstream feature development goes.

Signed-off-by: Kathleen Capella <kathleen.capella@arm.com>
Change-Id: Id00cdbd94466570a962d9c6956fda793758ee5d9
12 files changed