config: split iproto.advertise to several options

In brief:

* client -- for external clients
* peer -- for connections within the cluster, in particular for replicas
* sharding -- for routers and a rebalancer

See the instance_config.lua file for the details.

Part of #8810

NO_DOC=the old behavior was not released, the documentation request will
       be registered manually
NO_CHANGELOG=see NO_DOC