Ensure ML2 plugin package is installed

Some platforms have a package for ML2 plugin.

This change makes sure is it installed for those platforms when
ML2 plugin is used and configured.

Change-Id: I24c8eb7d17a462b63d2023027c90da7f876f7503
Closes-bug: #1264205
(cherry picked from commit b68158470abaeeb4431fc683994f2b7f8c71ea38)