Merge remote-tracking branch 'afaerber/tags/qom-devices-for-anthony' into staging

QOM infrastructure fixes for 1.7

* QOM memory leak fix

# gpg: Signature made Tue 19 Nov 2013 01:58:58 AM PST using RSA key ID 3E7E013F
# gpg: Can't check signature: public key not found

# By Vlad Yasevich
# Via Andreas Färber
* afaerber/tags/qom-devices-for-anthony:
  qom: Fix memory leak in object_property_set_link()