'Add subports to the trunk.
:param tenant_id: ID of the tenant.
:param trunk_id: ID of the trunk.
:param sub_ports: List of subport dictionaries to be added in format
{\'port_id\': <ID of neutron port for subport>,
\'segmentation_type\': \'vlan\',
\'segmentation_id\': <VLAN tag>}'

def trunk_add_subports(self, tenant_id, trunk_id, sub_ports):

    spec = {'tenant_id': tenant_id, 'sub_ports': sub_ports}
    trunk = self.client.trunk_add_subports(trunk_id, spec)
    sub_ports_to_remove = [sub_port for sub_port in trunk['sub_ports'] if (sub_port in sub_ports)]
    self.addCleanup(_safe_method(self.trunk_remove_subports), tenant_id, trunk_id, sub_ports_to_remove)
