u3: fixes bug in nock 6 compilation (increment uninitialized)
u3: fixes bug in nock 6 compilation (increment uninitialized)

ngzax/urbit,urbit/urbit,ngzax/urbit,ngzax/urbit,ngzax/urbit,urbit/urbit,ngzax/urbit,urbit/urbit,urbit/urbit,urbit/urbit,urbit/urbit,urbit/urbit,ngzax/urbit,ngzax/urbit