Bug#991809: A brief note about NIS installation

[Francesco Paolo Lovergine]

Package: release-notes
Severity: normal

NIS does not more use debconf for its initial installation. While existing
setups should smoothly upgrade to the new multi-package organization,
the recommended configuration way in bullseye is by following the nis-howto
document included in the `nis` meta-package for both clients and servers.