This patch adds support for passing FVP platform's topology
configuration to DTS files for compilation, which allows to
build DTBs with correct number of clusters and CPUs.
This removes non-existing clusters/CPUs from the compiled
device tree blob and fixes reported Linux errors when trying
to power on absent CPUs/PEs.
If DTS file is passed using FVP_HW_CONFIG_DTS build option from
the platform's makefile, FVP_CLUSTER_COUNT, FVP_MAX_CPUS_PER_CLUSTER
and FVP_MAX_PE_PER_CPU parameters are used, otherwise CI script will
use the default values from the corresponding DTS file.

Change-Id: Idcb45dc6ad5e3eaea18573aff1a01c9344404ab3
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>