Include bootstrap manifests in okd-rpms image

Assisted Installer doesn't pivot bootstrap node to machine-os, instead it creates a temporary overlay with OKD rpms and start bootkube. This makes it miss manifests from bootstrap/manifests and MCO is unable to find initial rendered-master- MC

Bootstrap manifests need to be included `okd-rpms` (possibly we should rename the image) and Assisted service would copy manifests to `/opt/openshift/openshift` on bootstrap node so stay as close as possible to bootstrap process