Disconnect timedout slave: regression introduced with diskless repl.

src/replication.c

@@ -2005,6 +2005,7 @@ void replicationCron(void) {
             {
                 redisLog(REDIS_WARNING, "Disconnecting timedout slave: %s",
                     replicationGetSlaveName(slave));
+                freeClient(slave);
             }
         }
     }