Revert "vm-configurator: Explicitly assign keyboard"

This reverts commit f425a36d4a459d690b246ec91fafa2e6d21c1d5a.
Revert "build: Require libvirt-gconfig >= 0.2.0"

This reverts commit 1423f6d7879fb8ce1fa96a6db863cbf82a03943f.