target-arm: Use the kernel's idea of MPIDR if we're using KVM

target-arm: Use the kernel's idea of MPIDR if we're using KVM

When we're using KVM, the kernel's internal idea of the MPIDR
affinity fields must match the values we tell it for the guest
vcpu cluster configuration in the device tree. Since at the moment
the kernel doesn't support letting userspace tell it the correct
affinity fields to use, we must read the kernel's view and
reflect that back in the device tree.

Signed-off-by: Shlomo Pongratz <shlomo.pongratz@huawei.com>
Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Message-id: 02f601d0a1e6$90c7d630$b2578290$@samsung.com
[PMM: Use a local #define rather than a global variable for
 the TCG ARM_CPUS_PER_CLUSTER setting. Tweak a comment. Update the
 commit message.]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>