lockdep: annotate journal_start()

On Fri, 2007-07-13 at 02:05 -0700, Andrew Morton wrote:

> Except lockdep doesn't know about journal_start(), which has ranking
> requirements similar to a semaphore.  

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>