switch kindnetd to generic sets

kindnetd is typically pre-compiled and not installed with "go get", kind development already uses much more recent go so requiring 1.18 for kindnetd is fine

Author: BenTheElder

images/kindnetd/cmd/kindnetd/main.go

@@ -252,7 +252,7 @@ func makeNodesReconciler(cniConfig *CNIConfigWriter, hostIP string, ipFamily IPF
 
 		// obtain the PodCIDR gateway
 		var nodeIPv4, nodeIPv6 string
-		for _, ip := range nodeIPs.List() {
+		for _, ip := range sets.List(nodeIPs) {
 			if isIPv6String(ip) {
 				nodeIPv6 = ip
 			} else {
@@ -285,8 +285,8 @@ func makeNodesReconciler(cniConfig *CNIConfigWriter, hostIP string, ipFamily IPF
 }
 
 // internalIPs returns the internal IP addresses for node
-func internalIPs(node corev1.Node) sets.String {
-	ips := sets.NewString()
+func internalIPs(node corev1.Node) sets.Set[string] {
+	ips := sets.New[string]()
 	// check the node.Status.Addresses
 	for _, address := range node.Status.Addresses {
 		if address.Type == "InternalIP" {

images/kindnetd/go.mod

@@ -1,6 +1,6 @@
 module sigs.k8s.io/kind/images/kindnetd
 
-go 1.17
+go 1.18
 
 require (
 	github.com/coreos/go-iptables v0.6.0