Networks settings are lost after reboot

1. Take a boot2Qt image and start the device
2. Set a static ip address
3. reboot the device

Expected result: the set ip address would be used by the device
Actual result: the settings before are used

Problem: the systemd overwrites the connman setting
Workaround: create a /etc/systemd/network/80-container-host0.network with the content:

[Match]
Name=eth0
[Network]
Address=10.9.21.245
Gateway=10.9.20.1
DNS=10.150.153.13