(ITS#8349) fix ppolicy issue

[hamano@osstech.co.jp]

Full_Name: HAMANO Tsukasa
Version: 2.4.43
OS: Linux
URL: https://www.osstech.co.jp/download/hamano/openldap/ppolicy_fix_pwdInHistory.patch
Submission from: (NULL) (240b:10:2640:bf0:290:4cff:fe0d:f43e)


We fixed several issue around ppolicy.

1) reduce pwdInHistory
If set pwdInHistory to 5 then reduce pwdInHistory to 3,
We expect to check password with three history, but ppolicy check
password with all pwdHistory attribute.

2) reduce pwdInHistory to zero
If set pwdInHistory to 5 then reduce pwdInHistory to 0,
We expect that ppolicy password checking will be disbale. but the
pwdHistory attribute are remains, so password checking is still
enabled.
We need to remove pwdHistory attribute.

Please apply the patch. Thank you.