azure: Wait for systemd booted
    
    The calling of systemd's utils during systemd boot may lead to
    unpredictable results. For example, if DBus(dbus-broker) service
    is not started then DBus request goes nowhere and eventually will
    be timeouted. So, it's safer to wait fully booted system.
    
    Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>