[PATCH] fix queues_count accounting in mqueue_delete_inode()

[PATCH] fix queues_count accounting in mqueue_delete_inode()

During mqueue_get_inode(), it's possible that kmalloc() of the
info->messages array will fail.  This failure mode will cause the
queues_count to be (incorrectly) decremented twice.  This patch uses
info->messages on mqueue_delete_inode() to determine whether the
mqueue was every truly created, and hence proper accounting is needed
on destruction.