kube-proxy remove todo: call iptables -S first when delete chain

Signed-off-by: cyclinder <qifeng.guo@daocloud.io>

pkg/util/iptables/iptables.go

@@ -285,7 +285,6 @@ func (runner *runner) DeleteChain(table Table, chain Chain) error {
 	runner.mu.Lock()
 	defer runner.mu.Unlock()
 
-	// TODO: we could call iptables -S first, ignore the output and check for non-zero return (more like DeleteRule)
 	out, err := runner.run(opDeleteChain, fullArgs)
 	if err != nil {
 		return fmt.Errorf("error deleting chain %q: %v: %s", chain, err, out)