jbd2: remove journal_clean_one_cp_list()

[ Upstream commit b98dba27

 ]

journal_clean_one_cp_list() and journal_shrink_one_cp_list() are almost
the same, so merge them into journal_shrink_one_cp_list(), remove the
nr_to_scan parameter, always scan and try to free the whole checkpoint
list.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230606135928.434610-4-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: 46f881b5

 ("jbd2: fix a race when checking checkpoint buffer busy")
Signed-off-by: Sasha Levin <sashal@kernel.org>