feat(rmmd): verify FEAT_MEC present before calling plat hoook

Some platforms do not support FEAT_MEC. Hence, they do not provide
an interface to update the update of the key corresponding to a
MECID.

This patch adds a condition in order to verify FEAT_MEC is present
before calling the corresponding platform hook, thus preventing it
from being called when the platform does not support the feature.

Change-Id: Ib1eb9e42f475e27ec31529569e888b93b207148c
Signed-off-by: Juan Pablo Conde <juanpablo.conde@arm.com>
3 files changed