When apply firewall group to a port with rule have dest port large than
source port, neutron-openvswitch-agent raise error 'port_max' is smaller
than 'port_min'. It because key 'port_range_max' is assigned by
source_port_range_max. Fix hard code 'port_range_max' to key_max.
Change-Id: I32d9efd857932547a13d275b8a4f294e03fe7535
Closes-Bug: #1869121
147116b7b1