Add sysadm_r to default SELinux user map order
    
    It is a standard SELinux user role included in RHEL (like
    user_r, staff_r, guest_r) and used quite often.
    
    Fixes: https://pagure.io/freeipa/issue/7658
    Signed-off-by: François Cami <fcami@redhat.com>
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>