All ocfs2 journal error handling and logging is based on buffer_heads,
and the owning inode and thus super_block can be retrieved through
bh->b_assoc_map->host.  Switch to using that to remove the last users
of bdev->bd_super.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Message-Id: <20230807112625.652089-4-hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>