Enable os-collect-config on boot for packages

When using packages with the tripleo-image-elements
os-collect-config is no longer started on boot causing
things not to be configured at all.

This was a regression in dad3c0ccf1d95111630362f6b022c2cb2e1c6885
where we made global use of package installs within the TripleO
image elements.

Change-Id: I001c3d24882b3a4817cac767a8b7535d6b9cf247
Closes-bug: #1392751
Merge "Enable os-collect-config on boot for packages"