Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2017-04-24' into staging

Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2017-04-24' into staging

Error reporting patches for 2017-04-24

# gpg: Signature made Mon 24 Apr 2017 08:16:34 BST
# gpg:                using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-error-2017-04-24:
  error: Apply error_propagate_null.cocci again
  qga: Make errp the last parameter of qga_vss_fsfreeze
  migration: Make errp the last parameter of local functions
  scsi: Make errp the last parameter of virtio_scsi_common_realize
  fdc: Make errp the last parameter of fdctrl_connect_drives
  nfs: Make errp the last parameter of nfs_client_open
  block: Make errp the last parameter of commit_active_start
  mirror: Make errp the last parameter of mirror_start_job
  crypto: Make errp the last parameter of functions
  block: Make errp the last parameter of bdrv_img_create
  socket: Make errp the last parameter of vsock_connect_saddr
  socket: Make errp the last parameter of unix_connect_saddr
  socket: Make errp the last parameter of inet_connect_saddr
  socket: Make errp the last parameter of socket_connect
  util/error: Fix leak in error_vprepend()

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