Configfile for distribution version is not applied

This manifests as a failure in CSIT [0].
The cause is the feature definition, not recognizing the configfile and wrapping it.

This is a regression from Carbon making distribution feature not readily usable, so this is a blocker.

[0] https://logs.opendaylight.org/releng/jenkins092/distribution-csit-1node-userfeatures-only-nitrogen/119/log.html.gz#s1-s3-t1-k3-k1-k3-k4-k1