Mark node as down if unable to dial control conn

Without this if during restart the resources assigned to node
change, the driver does not update this. That could lead to
outdated information about threads/shards.

Author: sylwiaszunejko

control.go

@@ -401,6 +401,9 @@ func (c *controlConn) attemptReconnectToAnyOfHosts(hosts []*HostInfo) (*Conn, er
 	for _, host := range hosts {
 		conn, err = c.session.connect(c.session.ctx, host, c)
 		if err != nil {
+			if c.session.cfg.ConvictionPolicy.AddFailure(err, host) {
+				c.session.handleNodeDown(host.ConnectAddress(), host.Port())
+			}
 			c.session.logger.Printf("gocql: unable to dial control conn %v:%v: %v\n", host.ConnectAddress(), host.Port(), err)
 			continue
 		}