Merge remote-tracking branch 'remotes/mdroth/tags/qga-pull-2017-11-20-tag' into staging

Merge remote-tracking branch 'remotes/mdroth/tags/qga-pull-2017-11-20-tag' into staging

qemu-ga patch queue for 2.11

* fix potential overflow in network interface stats reporting

# gpg: Signature made Mon 20 Nov 2017 20:56:05 GMT
# gpg:                using RSA key 0x3353C9CEF108B584
# gpg: Good signature from "Michael Roth <flukshun@gmail.com>"
# gpg:                 aka "Michael Roth <mdroth@utexas.edu>"
# gpg:                 aka "Michael Roth <mdroth@linux.vnet.ibm.com>"
# Primary key fingerprint: CEAC C9E1 5534 EBAB B82D  3FA0 3353 C9CE F108 B584

* remotes/mdroth/tags/qga-pull-2017-11-20-tag:
  qga: replace GetIfEntry with GetIfEntry2 for interface stats

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