Treat Filter as Dict in get_policies
Treat Filter as Dict in get_policies

Currently QoS plugin's get_policies doesnt check if the filter
is a dict or not, though similar checks exist in get_rule_types()
and get_policy_rules().
This patch adds the check so that if any consumer passes filters=None
then it is converted to a dict.

TrivialFix
Partial-Bug: #1711165

Change-Id: Id50674c44cd3720dcd8fd6d66361d937599f5992

mahak/neutron,eayunstack/neutron,mahak/neutron,openstack/neutron,huntxu/neutron,noironetworks/neutron,huntxu/neutron,openstack/neutron,noironetworks/neutron,mahak/neutron,openstack/neutron,eayunstack/neutron