The new ISA-agnostic interface is the PartitionManager.
We therefore make the PartitionFieldExtention private to the
Arm implementation of memory partitioning (FEAT_MPAM)
Any other partitioning implementation should override the
PartitionManager::readPacketPartitionID to provide a mean
for extracting partitioning data (partition_id) from the
incoming Packet.
With this commit we also define an MPAM MSC which is
supposed to be the partitioning manager for the
Memory System Component
Change-Id: I6959ace0c0cbca549dcc1aacd53dff223b5fe328
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>