Original code checked in output pool for missed wakeup avoidance, while waker
(batch_entropy_process) checked input pool which could result in a missed
wakeup.

- Move to wait_event_interruptible style

- Delete superfluous waitqueue
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>