Fix compiling e2e.test on macOS

Fix issue 122650 (regression in PR 122552)

```
$ make WHAT=test/e2e/e2e.test
+++ [0109 10:06:53] Building go targets for darwin/amd64
    k8s.io/kubernetes/test/e2e/e2e.test (test)
package k8s.io/kubernetes/test/e2e
        imports k8s.io/kubernetes/test/e2e/common
        imports k8s.io/kubernetes/test/e2e/common/node
        imports k8s.io/kubernetes/pkg/kubelet
        imports github.com/opencontainers/runc/libcontainer/userns: C source files not allowed when not using cgo or SWIG: userns_maps.c
!!! [0109 10:06:54] Call tree:
!!! [0109 10:06:54]  1: /Users/suda/gopath/src/k8s.io/kubernetes/hack/lib/golang.sh:948 kube::golang::build_binaries_for_platform(...)
!!! [0109 10:06:54]  2: hack/make-rules/build.sh:27 kube::golang::build_binaries(...)
!!! [0109 10:06:54] Call tree:
!!! [0109 10:06:54]  1: hack/make-rules/build.sh:27 kube::golang::build_binaries(...)
!!! [0109 10:06:54] Call tree:
!!! [0109 10:06:54]  1: hack/make-rules/build.sh:27 kube::golang::build_binaries(...)
make: *** [all] Error 1
```

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>

pkg/kubelet/cm/container_manager_linux.go

@@ -36,7 +36,6 @@ import (
 	"k8s.io/mount-utils"
 	utilpath "k8s.io/utils/path"
 
-	libcontaineruserns "github.com/opencontainers/runc/libcontainer/userns"
 	v1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
 	"k8s.io/apimachinery/pkg/types"
@@ -64,6 +63,7 @@ import (
 	"k8s.io/kubernetes/pkg/kubelet/pluginmanager/cache"
 	"k8s.io/kubernetes/pkg/kubelet/stats/pidlimit"
 	"k8s.io/kubernetes/pkg/kubelet/status"
+	"k8s.io/kubernetes/pkg/kubelet/userns/inuserns"
 	schedulerframework "k8s.io/kubernetes/pkg/scheduler/framework"
 	"k8s.io/kubernetes/pkg/util/oom"
 )
@@ -431,7 +431,7 @@ func setupKernelTunables(option KernelTunableBehavior) error {
 			klog.V(2).InfoS("Updating kernel flag", "flag", flag, "expectedValue", expectedValue, "actualValue", val)
 			err = sysctl.SetSysctl(flag, expectedValue)
 			if err != nil {
-				if libcontaineruserns.RunningInUserNS() {
+				if inuserns.RunningInUserNS() {
 					if utilfeature.DefaultFeatureGate.Enabled(kubefeatures.KubeletInUserNamespace) {
 						klog.V(2).InfoS("Updating kernel flag failed (running in UserNS, ignoring)", "flag", flag, "err", err)
 						continue

pkg/kubelet/kubelet.go

@@ -33,7 +33,6 @@ import (
 
 	cadvisorapi "github.com/google/cadvisor/info/v1"
 	"github.com/google/go-cmp/cmp"
-	libcontaineruserns "github.com/opencontainers/runc/libcontainer/userns"
 	"github.com/opencontainers/selinux/go-selinux"
 	"go.opentelemetry.io/otel/attribute"
 	semconv "go.opentelemetry.io/otel/semconv/v1.12.0"
@@ -110,6 +109,7 @@ import (
 	"k8s.io/kubernetes/pkg/kubelet/token"
 	kubetypes "k8s.io/kubernetes/pkg/kubelet/types"
 	"k8s.io/kubernetes/pkg/kubelet/userns"
+	"k8s.io/kubernetes/pkg/kubelet/userns/inuserns"
 	"k8s.io/kubernetes/pkg/kubelet/util"
 	"k8s.io/kubernetes/pkg/kubelet/util/manager"
 	"k8s.io/kubernetes/pkg/kubelet/util/queue"
@@ -471,7 +471,7 @@ func NewMainKubelet(kubeCfg *kubeletconfiginternal.KubeletConfiguration,
 
 	oomWatcher, err := oomwatcher.NewWatcher(kubeDeps.Recorder)
 	if err != nil {
-		if libcontaineruserns.RunningInUserNS() {
+		if inuserns.RunningInUserNS() {
 			if utilfeature.DefaultFeatureGate.Enabled(features.KubeletInUserNamespace) {
 				// oomwatcher.NewWatcher returns "open /dev/kmsg: operation not permitted" error,
 				// when running in a user namespace with sysctl value `kernel.dmesg_restrict=1`.

pkg/kubelet/userns/inuserns/inuserns_linux.go

@@ -0,0 +1,24 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package inuserns
+
+import libcontaineruserns "github.com/opencontainers/runc/libcontainer/userns"
+
+// RunningInUserNS detects whether the current process is running in a user namespace.
+func RunningInUserNS() bool {
+	return libcontaineruserns.RunningInUserNS()
+}

pkg/kubelet/userns/inuserns/inuserns_others.go

@@ -0,0 +1,25 @@
+//go:build !linux
+// +build !linux
+
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package inuserns
+
+// RunningInUserNS detects whether the current process is running in a user namespace.
+func RunningInUserNS() bool {
+	return false
+}