Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

Block pull request

 * Support -drive cache.direct=off live migration for POSIX files

# gpg: Signature made Sat 12 May 2018 10:27:51 BST
# gpg:                using RSA key 9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request:
  block/file-posix: add x-check-page-cache=on|off option
  block/file-posix: implement bdrv_co_invalidate_cache() on Linux
  checkpatch: reduce MAINTAINERS update message frequency
  checkpatch: emit a warning on file add/move/delete
  checkpatch: ignore email headers better
  checkpatch: check utf-8 content from a commit log when it's missing from charset
  checkpatch: add a --strict check for utf-8 in commit logs
  blockjob: drop block_job_pause/resume_all()

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

diff --cc scripts/checkpatch.pl
Simple merge