Merge remote-tracking branch 'remotes/armbru/tags/pull-misc-2018-10-10' into staging

Miscellaneous patches for 2018-10-10

# gpg: Signature made Wed 10 Oct 2018 07:03:10 BST
# gpg:                using RSA key 3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-misc-2018-10-10:
  ivshmem: Fix unplug of device "ivshmem-plain"
  libqtest: Inline g_assert_no_errno()
  tests: Restore check-qdict unit test
  qapi/misc.json: Remove superfluous words in CpuModelExpansionType
  tests/check-qjson: fix a leak

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