SFC plugin: fix flow classifier list display
SFC plugin: fix flow classifier list display

Current code displays "<type 'type'>[port]:xx" for
source/destination ports:

$ openstack sfc flow classifier list -c Summary -f value
protocol: UDP,
<type 'type'>[port]: 192.168.0.14/32[any:any],
<type 'type'>[port]: 192.168.0.16/32[any:any],
neutron_source_port: 5c196983-c319-41d7-9af0-02301ed85513,
neutron_destination_port: None,
l7_parameters: {}

Change-Id: Ia5c772d48b22d4007dad8645cbfd2ea81cbb80ad
Closes-Bug: #1706379

noironetworks/python-neutronclient,huntxu/python-neutronclient,huntxu/python-neutronclient,openstack/python-neutronclient,noironetworks/python-neutronclient,openstack/python-neutronclient