Ticket 49224 - without --prefix, $prefixdir would be NONE in defaults.
    
    Bug Description:  In the handling of $prefix, we set $prefix dir early
    in the process, but later configure changes it to $ac_default_prefix
    if $prefix == NONE.
    
    Fix Description:  Check if $prefix is none, and update the value
    based on $ac_default_prefix from that instead.
    
    https://pagure.io/389-ds-base/issue/49224
    
    Author: wibrown
    
    Review by: Ilias95, mreynolds (Thanks!)