fs/ntfs3: Restore ntfs_xattr_get_acl and ntfs_xattr_set_acl functions

Apparently we need to maintain these functions with
ntfs_get_acl_ex and ntfs_set_acl_ex.
This commit fixes xfstest generic/099
Fixes: 95dd8b2c ("fs/ntfs3: Remove unnecessary functions")

Reviewed-by: Kari Argillander <kari.argillander@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>