Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2018-08-27-v2' into...

Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2018-08-27-v2' into staging

Error reporting patches for 2018-08-27

# gpg: Signature made Mon 27 Aug 2018 14:18:15 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-error-2018-08-27-v2:
  intel-iommu: replace more vtd_err_* traces
  intel-iommu: start to use error_report_once
  qemu-error: introduce {error|warn}_report_once

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