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

QOM infrastructure fixes and device conversions

* Dynamic class properties
* Property iterator cleanup
* Device hot-unplug ID race fix

# gpg: Signature made Mon 18 Jan 2016 17:27:01 GMT using RSA key ID 3E7E013F
# gpg: Good signature from "Andreas Färber <[email protected]>"
# gpg:                 aka "Andreas Färber <[email protected]>"

* remotes/afaerber/tags/qom-devices-for-peter:
  MAINTAINERS: Fix sPAPR entry heading
  qdev: Free QemuOpts when the QOM path goes away
  qom: Change object property iterator API contract
  qom: Allow properties to be registered against classes

Signed-off-by: Peter Maydell <[email protected]>