[PATCH] idle threads should have a sane ->timestamp value

Idle threads should have a sane ->timestamp value, to avoid init kernel
thread(s) from inheriting it and causing miscalculations in
try_to_wake_up().

Reported-by: Mike Galbraith <efault@gmx.de>.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --cc kernel/sched.c
Simple merge