gossip: Make maybe_enable_features public
gossip: Make maybe_enable_features public

It will be needed by storage_service.

duarten/scylla,scylladb/scylla,scylladb/scylla,duarten/scylla,avikivity/scylla,avikivity/scylla,scylladb/scylla,avikivity/scylla,duarten/scylla,scylladb/scylla