rpc: remove redundant server_socket destruction.
rpc: remove redundant server_socket destruction.

abort_accept() handles it now.

cloudius-systems/seastar,cloudius-systems/seastar,dreamsxin/seastar,syuu1228/seastar,avikivity/seastar,dreamsxin/seastar,scylladb/seastar,cloudius-systems/seastar,scylladb/seastar,syuu1228/seastar,avikivity/seastar,scylladb/seastar,avikivity/seastar,syuu1228/seastar,dreamsxin/seastar