Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches:

- qcow2: Fix data corruption bug that is triggered in partial cluster
  allocation with default options
- qapi: add support for blkreplay driver
- doc: Describe missing generic -blockdev options
- iotests: Fix 118 when run as root
- Minor code cleanups

# gpg: Signature made Fri 25 Oct 2019 14:19:04 BST
# gpg:                using RSA key 7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74  56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream:
  qcow2: Fix corruption bug in qcow2_detect_metadata_preallocation()
  coroutine: Add qemu_co_mutex_assert_locked()
  doc: Describe missing generic -blockdev options
  block/backup: drop dead code from backup_job_create
  blockdev: Use error_report() in hmp_commit()
  iotests: Skip read-only cases in 118 when run as root
  qapi: add support for blkreplay driver

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