Use SetNotifyFd instead, with the hope that someday someone will come
fix this to be more efficient -- right now, the wakeup handler is
doing the event reading, instead of the notify callback.
v2: no need to patch dmxsigio.c as it has been removed.
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>