Ticket 50195 - improve selinux error messages in interactive
    
    Bug Description: During an interactive install, the selinux
    module if not found would produce many error messages that
    were not necessary.
    
    Fix Description: Warn the user at the start of the install
    that selinux isn't found, and allow them to continue
    
    https://pagure.io/389-ds-base/issue/50195
    
    Author: William Brown <william@blackhats.net.au>
    
    Review by: spichugi (Thanks!)