no need to save container state here

it is already being saved (with a lock held) on the subsequent
operations.

Signed-off-by: Fabio Kung <fabio.kung@gmail.com>

container/container_unix.go

@@ -332,11 +332,6 @@ func (container *Container) UpdateContainer(hostConfig *containertypes.HostConfi
 		container.HostConfig.RestartPolicy = hostConfig.RestartPolicy
 	}
 
-	if err := container.ToDisk(); err != nil {
-		logrus.Errorf("Error saving updated container: %v", err)
-		return err
-	}
-
 	return nil
 }