PPC: Enable to use PAPR with PR style KVM

PPC: Enable to use PAPR with PR style KVM

When running PR style KVM, we need to tell the kernel that we want
to run in PAPR mode now. This means that we need to pass some more
register information down and enable papr mode. We also need to align
the HTAB to htab_size boundary.

Using this patch, -M pseries works with kvm even on non-hv kvm
implementations, as long as the preceding kernel patches are in.

Signed-off-by: Alexander Graf <agraf@suse.de>
---

v1 -> v2:

  - match on CONFIG_PSERIES

v2 -> v3:

  - remove HIOR pieces from PAPR patch (ABI breakage)