Merge remote-tracking branch 'remotes/berrange/tags/min-glib-pull-request' into staging

Merge remote-tracking branch 'remotes/berrange/tags/min-glib-pull-request' into staging

glib: update the min required version

This updates the minimum required glib version to 2.40

# gpg: Signature made Fri 29 Jun 2018 12:24:58 BST
# gpg:                using RSA key BE86EBB415104FDF
# gpg: Good signature from "Daniel P. Berrange <dan@berrange.com>"
# gpg:                 aka "Daniel P. Berrange <berrange@redhat.com>"
# Primary key fingerprint: DAF3 A6FD B26B 6291 2D0E  8E3F BE86 EBB4 1510 4FDF

* remotes/berrange/tags/min-glib-pull-request:
  glib: enforce the minimum required version and warn about old APIs
  glib: bump min required glib library version to 2.40
  util: remove redundant include of glib.h and add osdep.h

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