[PATCH] Minor workqueue.c cleanup

[PATCH] Minor workqueue.c cleanup

From: Rusty Russell <rusty@rustcorp.com.au>

Move duplicated code to __queue_work(), and don't set the CPU for
queue_delayed_work() until the timer goes off.  The second one only has an
effect on CONFIG_HOTPLUG_CPU where the CPU goes down and the timer goes off
on a different CPU than it was scheduled on.