This tool by design is called as root, so try to:
- switch to normal user if possible
- fix file permissions afterwards - if not
QubesOS/qubes-issues#2412
This is intended to call to finish template installation/removal.
Template RPM package is basically container for root.img, nothing more.
Other parts needs to be generated after root.img extraction. Previously
it was open coded in rpm post-install script, but lets keep it as qvm
tool to ease supporting multiple version in template builder
QubesOS/qubes-issues#2412