create_ovs_vif_port has six required arguments:
* bridge
* dev
* iface_id
* mac
* instance_id
* mtu
And an optional argument - timeout.
However calls to create_ovs_vif_port only supplied five of six required
arguments and the optional argument, and mocks to the call also had the
incorrect number of arguments. Therefore the unit tests passed but any
code that actually called create_ovs_vif_port would have thrown an
error.
Change-Id: Ic165557da57cf6df1fd39309b16e0a89a02df16d