ocfs2: use bitmap API in fill_node_map

Pass bits directly into fill_node_map helper and use bitmap API directly
to simplify code.

Link: https://lkml.kernel.org/r/20221007124846.186453-2-joseph.qi@linux.alibaba.com


Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>