mambo: Create multiple chips when we have multiple CPUs
mambo: Create multiple chips when we have multiple CPUs

Currently when we boot mambo with multiple CPUs, we create multiple CPU nodes in
the device tree, and each claims to be on a separate chip.

However we don't create multiple xscom nodes, which means skiboot only knows
about a single chip, and all CPUs end up on it. At the moment mambo is not able
to create multiple xscom controllers. We can create fake ones, just by faking
the device tree up, but that seems uglier than this solution.

So create a mambo-chip for each CPU other than 0, to tell skiboot we want a
separate chip created. This then enables Linux to see multiple chips:

  smp: Brought up 2 nodes, 2 CPUs
  numa: Node 0 CPUs: 0
  numa: Node 1 CPUs: 1

Signed-off-by: Michael Ellerman <864f124608374e06e4da1fa5d2e47ed839b95411@ellerman.id.au>
Signed-off-by: Stewart Smith <ec31ab75ddf977353c8f660f92ea8b23f64aef25@linux.vnet.ibm.com>

legoater/skiboot,mikey/skiboot,stewart-ibm/skiboot,qemu/skiboot,open-power/skiboot,legoater/skiboot,open-power/skiboot,shenki/skiboot,shenki/skiboot,qemu/skiboot,legoater/skiboot,shenki/skiboot,qemu/skiboot,mikey/skiboot,stewart-ibm/skiboot,legoater/skiboot,legoater/skiboot,qemu/skiboot,mikey/skiboot,open-power/skiboot,qemu/skiboot,shenki/skiboot,stewart-ibm/skiboot,open-power/skiboot,shenki/skiboot,open-power/skiboot