Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2020-10-09' into staging

Error reporting patches for 2020-10-09

# gpg: Signature made Fri 09 Oct 2020 07:45:17 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-error-2020-10-09:
  error: Use error_fatal to simplify obvious fatal errors (again)
  error: Remove NULL checks on error_propagate() calls (again)

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