Merge remote-tracking branch 'remotes/berrange/tags/pull-sockets-2017-07-11-3' into staging

Merge sockets 2017/07/11 v3

# gpg: Signature made Fri 14 Jul 2017 16:09:03 BST
# gpg:                using RSA key 0xBE86EBB415104FDF
# gpg: Good signature from "Daniel P. Berrange <dan@berrange.com>"
# gpg:                 aka "Daniel P. Berrange <berrange@redhat.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: DAF3 A6FD B26B 6291 2D0E  8E3F BE86 EBB4 1510 4FDF

* remotes/berrange/tags/pull-sockets-2017-07-11-3:
  io: preserve ipv4/ipv6 flags when resolving InetSocketAddress
  sockets: ensure we don't accept IPv4 clients when IPv4 is disabled
  sockets: don't block IPv4 clients when listening on "::"
  sockets: ensure we can bind to both ipv4 & ipv6 separately

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