Currently we read VPD values (e.g. should_send_rlz_ping) through Statisticsprovider. This design was intentional because:

1) Statisticsprovider was (at least partly) designed to read VPD values.

2) We generally try to add new d-bus calls unless absolutely necessary because it has its own complexity and cost.

But we should rethink about this, given that we've seen regressions such as issue 874286. We could add a new d-bus call to read VPD values at this point.

Targeted at M71, but will prioritize the market segmentation work over this.