Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2021-08-26' into staging

Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2021-08-26' into staging

Error reporting patches for 2021-08-26

# gpg: Signature made Thu 26 Aug 2021 16:17:05 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-2021-08-26:
  vl: Clean up -smp error handling
  Remove superfluous ERRP_GUARD()
  vhost: Clean up how VhostOpts method vhost_backend_init() fails
  vhost: Clean up how VhostOpts method vhost_get_config() fails
  microvm: Drop dead error handling in microvm_machine_state_init()
  migration: Handle migration_incoming_setup() errors consistently
  migration: Unify failure check for migrate_add_blocker()
  whpx nvmm: Drop useless migrate_del_blocker()
  vfio: Avoid error_propagate() after migrate_add_blocker()
  i386: Never free migration blocker objects instead of sometimes
  vhost-scsi: Plug memory leak on migrate_add_blocker() failure
  multi-process: Fix pci_proxy_dev_realize() error handling
  spapr: Explain purpose of ->fwnmi_migration_blocker more clearly
  spapr: Plug memory leak when we can't add a migration blocker
  error: Use error_fatal to simplify obvious fatal errors (again)

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