client: Remove userid parameter from isr_srun()
client: Remove userid parameter from isr_srun()

- Remove $userid parameter from isr_srun(), since it's just a copy of the
$userid global

cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr