Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-2.12-20180121' into staging

ppc patch queue 2018-01-21

This request supersedes the one from 2018-01-19.  The only difference
is that the patch deprecating ppcemb-softmmu, and thereby creating
many annying warnings from make check has been removed.

Highlights are:
  * Significant TCG speedup by optimizing cmp generation
  * Fix a regression caused by recent change to set compat mode on
    hotplugged cpus
  * Cleanup of default configs
  * Some implementation of msgsnd/msgrcv instructions for server chips

# gpg: Signature made Sun 21 Jan 2018 05:30:54 GMT
# gpg:                using RSA key 0x6C38CACA20D9B392
# gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>"
# gpg:                 aka "David Gibson (Red Hat) <dgibson@redhat.com>"
# gpg:                 aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>"
# gpg:                 aka "David Gibson (kernel.org) <dwg@kernel.org>"
# Primary key fingerprint: 75F4 6586 AE61 A66C C44E  87DC 6C38 CACA 20D9 B392

* remotes/dgibson/tags/ppc-for-2.12-20180121:
  target/ppc/spapr_caps: Add macro to generate spapr_caps migration vmstate
  target/ppc: add support for hypervisor doorbells on book3s CPUs
  sii3112: Add explicit type casts to avoid unintended sign extension
  sm501: Add missing break to case
  target-ppc: optimize cmp translation
  spapr: fix device tree properties when using compatibility mode
  spapr: drop duplicate variable in spapr_core_plug()
  target/ppc: msgsnd and msgclr instructions need hypervisor privilege
  target/ppc: fix doorbell and hypervisor doorbell definitions
  hw/ppc/Makefile: Add a way to disable the PPC4xx boards
  default-configs/ppc-softmmu: Restructure the switches according to the machines
  default-configs/ppc64-softmmu: Include 32-bit configs instead of copying them

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>