lockdep: Fix up warning

On Sun, 2011-07-24 at 21:06 -0400, Arnaud Lacombe wrote:

> /src/linux/linux/kernel/lockdep.c: In function 'mark_held_locks':
> /src/linux/linux/kernel/lockdep.c:2471:31: warning: comparison of
> distinct pointer types lacks a cast

The warning is harmless in this case, but the below makes it go away.
Reported-by: Arnaud Lacombe <lacombar@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1311588599.2617.56.camel@laptopSigned-off-by: Ingo Molnar <mingo@elte.hu>

kernel/lockdep.c

@@ -2468,7 +2468,7 @@ mark_held_locks(struct task_struct *curr, enum mark_type mark)
 
 		BUG_ON(usage_bit >= LOCK_USAGE_STATES);
 
-		if (hlock_class(hlock)->key == &__lockdep_no_validate__)
+		if (hlock_class(hlock)->key == __lockdep_no_validate__.subkeys)
 			continue;
 
 		if (!mark_lock(curr, hlock, usage_bit))