ubifs: rename_whiteout: correct old_dir size computing

hulk inclusion
category: bugfix
bugzilla: 186191, https://gitee.com/openeuler/kernel/issues/I4U4SQ


CVE: NA

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When renaming the whiteout file, the old whiteout file is not deleted.
Therefore, we add the old dentry size to the old dir like XFS.
Otherwise, an error may be reported due to `fscki->calc_sz != fscki->size`
in check_indes.

Fixes: 9e0a1fff ("ubifs: Implement RENAME_WHITEOUT")
Reported-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>