fix(rme): use RMM shared buffer for attest SMCs

Use the RMM shared buffer to attestation token and signing key SMCs.

Signed-off-by: Javier Almansa Sobrino <javier.almansasobrino@arm.com>
Change-Id: I313838b26d3d9334fb0fe8cd4b229a326440d2f4
5 files changed