Updated openstack/openstack
Project: openstack/neutron  431937ce5ac897c3d5b6efd66bc6b5326190ee57

Move _filter_non_model_columns method to CommonDbMixin

Such way other non-core plugins may avoid duplicating this small
piece of code.

Change-Id: I00ae0b590fc2ad46d3667d18f29fccb5b40bde82