Merge pull request #30802 from MHBauer/ensure-mounter

Automatic merge from submit-queue

ensure pkg/util/mount compiles & crosses

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**What this PR does / why we need it**:
osx doesn't build
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #30795

**Special notes for your reviewer**:

**Release note**:
```release-note-none
```

 - move compile time check from linux code to generic code
 - remove duplication of #30724 and #30666 to resolve #30795

pkg/util/mount/mount.go

@@ -51,6 +51,10 @@ type Interface interface {
 	GetDeviceNameFromMount(mountPath, pluginDir string) (string, error)
 }
 
+// Compile-time check to ensure all Mounter implementations satisfy
+// the mount interface
+var _ Interface = &Mounter{}
+
 // This represents a single line in /proc/mounts or /etc/fstab.
 type MountPoint struct {
 	Device string

pkg/util/mount/mount_linux.go

@@ -54,8 +54,6 @@ const (
 // kubelet is running in the host's root mount namespace.
 type Mounter struct{}
 
-var _ = Interface(&Mounter{})
-
 // Mount mounts source to target as fstype with given options. 'source' and 'fstype' must
 // be an emtpy string in case it's not required, e.g. for remount, or for auto filesystem
 // type, where kernel handles fs type for you. The mount 'options' is a list of options,