I had a look at the diff file for occurrences of williams_input_port_0_r (which appears to be what is giving compile errors), and replaced the two instances that I found with stargate_input_port_0_r and defender_input_port_0_r in the respective sections.
After applying this modified patch, the compile succeeds, and I get the option for 8-way joystick in defender.
Not sure whether this breaks anything else?
Martin