DietPi-Automation | Allow first run update and setup without manual login

[MichaIng]

Ref: https://dietpi.com/phpbb/viewtopic.php?f=11&t=5457

• Either allow dietpi-update and dietpi-software to run without login: Replace $HOME and ~/ by /root and test/check other similar cases where commands/variables might need login before being available.
• Or place [email protected] autologin drop-in, as we do with dietpi-autostart console autologin.

Password change (at least in case dietpi is still used) and license accept prompt should still be done on first login.

[MichaIng]

First step, which anyway makes sense independently from this request, replaced $HOME/~ with /root since we force root user to run the script anyway and /root is his home even defined in FHS: 9e9c765

[MichaIng]

Another vote: #3553

[MichaIng]

I actually seems to work now, although not sure what has changed. The [email protected] override is created during dietpi-firstboot.service execution for a while already and at least on my last tests it was effective on first boot already, even without an explicit systemctl daemon-reload. Requires some more tests on different devices (different boot speeds and orders as of hardware initiation).