Requesting dbus name after finishing initialization

I did synthetic test by adding a sleep(Duration::from_secs(20)) right before all Ctrl commands, without this commit systemd doesn't wait after running systemctl start asusd so in really some edge cases this can lead to xorg start before CtrlGraphics is finished. With that commit as expected systemctl start asusd in my test takes exactly 22s (2s ExecStartPre + 20s from my sleep). This should help to eliminated such rare edge cases where xorg starts before CtrlGraphics is finished.