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* Rootfs dir is created during container creation not during bundle
  creation
* Add support for v2
* UnmountAll is a no-op when the path to unmount (i.e. the rootfs dir)
  does not exist or is invalid

Co-authored-by: Danail Branekov <danailster@gmail.com>
Signed-off-by: Georgi Sabev <georgethebeatle@gmail.com>

runtime/v1/linux/bundle.go

@@ -65,9 +65,6 @@ func newBundle(id, path, workDir string, spec []byte) (b *bundle, err error) {
 			os.RemoveAll(workDir)
 		}
 	}()
-	if err := os.Mkdir(filepath.Join(path, "rootfs"), 0711); err != nil {
-		return nil, err
-	}
 	err = ioutil.WriteFile(filepath.Join(path, configFilename), spec, 0666)
 	return &bundle{
 		id:      id,