Merge remote-tracking branch 'remotes/vivier2/tags/trivial-branch-pull-request' into...

Documentation update and a typo fix

# gpg: Signature made Tue 22 Oct 2019 09:25:35 BST
# gpg:                using RSA key CD2F75DDC8E3A4DC2E4F5173F30C38BD3F2FBE3C
# gpg:                issuer "[email protected]"
# gpg: Good signature from "Laurent Vivier <[email protected]>" [full]
# gpg:                 aka "Laurent Vivier <[email protected]>" [full]
# gpg:                 aka "Laurent Vivier (Red Hat) <[email protected]>" [full]
# Primary key fingerprint: CD2F 75DD C8E3 A4DC 2E4F  5173 F30C 38BD 3F2F BE3C

* remotes/vivier2/tags/trivial-branch-pull-request:
  tests/migration: fix a typo in comment
  qemu-doc: Remove paragraph about requiring a HD image with -kernel

Signed-off-by: Peter Maydell <[email protected]>