Merge remote-tracking branch 'remotes/armbru/tags/pull-misc-2021-05-12' into staging

Merge remote-tracking branch 'remotes/armbru/tags/pull-misc-2021-05-12' into staging

Miscellaneous patches for 2021-05-12

# gpg: Signature made Wed 12 May 2021 17:22:15 BST
# gpg:                using RSA key 354BC8B3D7EB2A6B68674E5F3870B400EB918653
# gpg:                issuer "armbru@redhat.com"
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full]
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>" [full]
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-misc-2021-05-12:
  Drop the deprecated unicore32 target
  Drop the deprecated lm32 target
  block: Drop the sheepdog block driver
  Remove the deprecated moxie target
  monitor/qmp: fix race on CHR_EVENT_CLOSED without OOB

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