After the fix for
MDEV-4795, server can be built on a system with a wrong boost version, and this is good.
However, the debian packages still fail to build, because OQGRAPH is absent while it is expected. As a result, we don't provide 5.5 packages for Trusty at all, and it is getting bad since Trusty is going GA soon.
Either we need to downgrade the VMs, or make ha_oqgraph optional (if it's possible).