Description of problem:
unable to remove slave from bond and use it to create another bond in one request.

How reproducible:
seems to be affected by nic status. If nic is down, operation seems to succeed.

Steps to Reproduce:
1. setup host with 4 nics. Use 3 of them to create bond.
2. in ovirt-engine UI detach one slave and create bond using this nic and fourth nic. Confirm dialog.


Actual results:
Error while executing action HostSetupNetworks: Interface already in use

Expected results:
operation succeeds.

Additional info:

<JsonRpcRequest id: "29681444-f287-4e7c-b11d-4ef0d936a125", method: Host.setupNetworks, params: {"networks":{},"bondings":{bond0={nics=[dummy_31, dummy_30], options=mode=4 miimon=100}, bond1={nics=[dummy_32, dummy_40], options=mode=4 miimon=100}},"options":{connectivityTimeout=120, connectivityCheck=true}}>


MainProcess|jsonrpc.Executor/4::ERROR::2015-11-19 09:36:02,656::supervdsmServer::118::SuperVdsm.ServerCallback::(wrapper) Error in setupNetworks
Traceback (most recent call last):
  File "/usr/share/vdsm/supervdsmServer", line 116, in wrapper
    res = func(*args, **kwargs)
  File "/usr/share/vdsm/supervdsmServer", line 241, in setupNetworks
    return setupNetworks(networks, bondings, **options)
  File "/usr/share/vdsm/network/api.py", line 944, in setupNetworks
    _handleBondings(bondings, configurator, in_rollback)
  File "/usr/share/vdsm/network/api.py", line 691, in _handleBondings
    destroyOnMasterRemoval='remove' in attrs)
  File "/usr/share/vdsm/network/models.py", line 280, in objectivize
    mtu, _netinfo)
  File "/usr/share/vdsm/network/models.py", line 269, in _objectivizeSlaves
    (nic, nicVlans or nicNet or nicBond))
ConfigNetworkError: (24, u'nic dummy_31 already used by bond0')