Implement powersave_nap sysctl, like ppc32.  This allows us to disable the
nap function which is useful when profiling with oprofile (to get an
accurate count of idle time).
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>