fs/ntfs3: Refactor ntfs_get_acl_ex for better readability

mainline inclusion
from mainline-v5.15
commit 0bd5fdb8
category: feature
bugzilla:
https://gitee.com/openeuler/kernel/issues/I4G67J?from=project-issue


CVE: NA

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We can safely move set_cached_acl because it works with NULL acl too.

Reviewed-by: Kari Argillander <kari.argillander@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Yin Xiujiang <yinxiujiang@kylinos.cn>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Acked-by: Hou Tao <houtao1@huawei.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>