r694: - Fix locking for "isr disconnect"
r694: - Fix locking for "isr disconnect"

- Pull the hoard retry logic from hoard() into a separate function
do_hoard()

- Have disconnect() use do_hoard() rather than calling isr_hoard() directly
(and not checking the return value).  This prevents "isr disconnect" from
reporting success when a network timeout occurs or ctrl-C is pressed.

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