[ATALK] aarp: replace schedule_timeout() with msleep()

From: Nishanth Aravamudan <nacc@us.ibm.com>

Use msleep() instead of schedule_timeout() to guarantee the task
delays as expected. The current code is not wrong, but it does not account for
early return due to signals, so I think msleep() should be appropriate.

Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: David S. Miller <davem@davemloft.net>