Remove the file /usr/share/indi/indi_piface_focuser.xml should make it work, assuming you are not using it.
I also removed /usr/share/indi/indi_piface_relay.xml, as well, and cannot remember which one did it.
I have just updated astroberry-piface driver and updated related xml files. Download and install
new version
. I would appreciate feedback after you test it. Apparently INDI xml syntax changed in the meantime so I needed to update it.