Correct binding delete function signature
Correct binding delete function signature

Change-Id: Ife0860a624dc9860ccb40a7814e35521041ba9a8

yamt/networking-midonet,JoeMido/networking-midonet,midokura/python-neutron-plugin-midonet,yamt/networking-midonet,JoeMido/networking-midonet,midonet/python-neutron-plugin-midonet,midonet/python-neutron-plugin-midonet,midokura/python-neutron-plugin-midonet