ocfs2: avoid a pointless delay in o2cb_cluster_check()

Fix an off-by-one when attempting to avoid an msleep() on the final loop
iteration.

Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>