Merge remote-tracking branch 'remotes/ericb/tags/pull-qapi-2018-04-10' into staging

Merge remote-tracking branch 'remotes/ericb/tags/pull-qapi-2018-04-10' into staging

qapi patches for 2018-04-10

- Peter Xu: iotests: fix wait_until_completed()
- Peter Xu: iothread: workaround glib bug which hangs qmp-test
- Peter Xu: monitor: bind dispatch bh to iohandler context

# gpg: Signature made Tue 10 Apr 2018 14:15:09 BST
# gpg:                using RSA key A7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>"
# gpg:                 aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>"
# gpg:                 aka "[jpeg image of size 6874]"
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2  F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-qapi-2018-04-10:
  monitor: bind dispatch bh to iohandler context
  iothread: workaround glib bug which hangs qmp-test
  iotests: fix wait_until_completed()

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