Improves sssd.conf handling during ipa-client uninstall
    
    The sssd.conf file is no longer left behind in case sssd was not
    configured before the installation. However, the patch goes behind
    the scope of this ticked and improves the handling of sssd.conf
    during the ipa-client-install --uninstall in general.
    
    The current behaviour (well documented in source code) is as follows:
      - In general, the IPA domain is simply removed from the sssd.conf
        file, instead of sssd.conf being rewritten from the backup. This
        preserves any domains added after installation.
    
      - If sssd.conf existed before the installation, it is restored to
        sssd.conf.bkp. However, any IPA domains from pre-installation
        sssd.conf should have been merged during the installation.
    
      - If sssd.conf did not exist before the installation, and no other
        domains than IPA domain exist in it, the patch makes sure that
        sssd.conf is moved to sssd.conf.deleted so user experiences no
        crash during any next installation due to its existence.
    
    https://fedorahosted.org/freeipa/ticket/2740