Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-2.10-20170725' into staging

ppc patch queue 2017-07-25

Last pull request for the 2.10 hard freeze, and correspondingly small.
There are a handful of bugfixes here plus an update for the "pseries"
guest firmware (SLOF).

This is later than ideal for a guest firmware update.  However, this
does include a number of fixes in that guest firmware, so I think it's
worth the risk of squeezing this in just before the hard freeze.

# gpg: Signature made Tue 25 Jul 2017 06:43:14 BST
# 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-2.10-20170725:
  pseries: Update SLOF firmware image
  spapr: Fix QEMU abort during memory unplug
  spapr/htab: fix savevm
  spapr_pci: Fix obsolete comment about MSIX encoding in addr/data

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