Fix lint errors

dns/transport/dhcp/dhcp.go

@@ -222,7 +222,7 @@ func (t *Transport) fetchServers0(ctx context.Context, iface *control.Interface)
 		packetConn net.PacketConn
 		err        error
 	)
-	for i := 0; i < 5; i++ {
+	for range 5 {
 		packetConn, err = listener.ListenPacket(t.ctx, "udp4", listenAddr)
 		if err == nil || !errors.Is(err, syscall.EADDRINUSE) {
 			break

dns/transport/dhcp/dhcp_shared.go

@@ -72,7 +72,7 @@ func (t *Transport) tryOneName(ctx context.Context, servers []M.Socksaddr, fqdn
 	sLen := len(servers)
 	var lastErr error
 	for i := 0; i < t.attempts; i++ {
-		for j := 0; j < sLen; j++ {
+		for j := range sLen {
 			server := servers[j]
 			question := message.Question[0]
 			question.Name = fqdn