While plugging vif, VIFDriver in Nova follows "ovs_hybrid_plug" and
"port_filter" in "binding:vif_detail" which is passed from Neutron, but
those are always true. This patch make ML2 OVS mech driver set those
param depends on enable_security_group flag. It enables users to avoid
ovs_hybrid plugging.
This patch also fixes the same issue in the following plugins/drivers:
* NEC Plugin
* BigSwitch Plugin
* Ryu Plugin
* ML2 Plugin - OFAgent Mech Driver
Closes-Bug: #1336624
Change-Id: I2b7fb526a6f1b730ad65289307b24fd28b996e1b
(cherry picked from commit e73f8da072)