ipa-client-automount: always restore nsswitch.conf at uninstall time
    
    ipa-client-automount used to only restore nsswitch.conf when sssd was not
    used. However authselect's default profile is now sssd so always restore
    nsswitch.conf's automount configuration to 'files sssd'.
    Note that the behavior seen before commit:
    a0e846f56c8de3b549d1d284087131da13135e34
    would always restore nsswitch.conf to the previous state which in some cases
    was wrong.
    
    Fixes: https://pagure.io/freeipa/issue/8038
    Signed-off-by: François Cami <fcami@redhat.com>
    Reviewed-By: Francois Cami <fcami@redhat.com>
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>