arch_topology: Set cluster identifier in each core/thread from /cpu-map

arch_topology: Set cluster identifier in each core/thread from /cpu-map

Let us set the cluster identifier as parsed from the device tree
cluster nodes within /cpu-map.

We don't support nesting of clusters yet as there are no real hardware
to support clusters of clusters.

Link: https://lore.kernel.org/r/20220704101605.1318280-19-sudeep.holla@arm.com
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>