gossip: cleanup application_state
gossip: cleanup application_state

Drop the unused one.

Message-Id: <cf4adfd6cacbcdf39a9b2f953495da5da0e55553@scylladb.com>

avikivity/scylla,kjniemi/scylla,duarten/scylla,scylladb/scylla,raphaelsc/scylla,duarten/scylla,raphaelsc/scylla,kjniemi/scylla,kjniemi/scylla,duarten/scylla,scylladb/scylla,scylladb/scylla,scylladb/scylla,avikivity/scylla,raphaelsc/scylla,avikivity/scylla