Android - Disable Cyanogen Privacy Guard from Shell

Removing /data/system/appops.xml from TWRP (recovery) helped.

Instead of removing /data/system/appops.xml you can also edit it, at least if only the permissions to "Google Play Services" are the problem.

As I didn't want to re-configure all the app permissions, I downloaded appops.xml through adb (adb pull /data/system/appops.xml) and removed the section

<pkg n="">

This just removes all settings for Google Play Services. After that I uploaded the edited file again (adb push appops.xml /data/system/appops.xml) and everything works after restart.