Running integration tests on Overlayfs fail

Tests that fail:

```
--- FAIL: TestSaveAndLoadRepoFlags (0.47s)
    docker_cli_save_load_test.go:266: inspect is not the same after a save / load
--- FAIL: TestSaveDirectoryPermissions (1.02s)
    docker_cli_save_load_test.go:425: failed to find the layer with the right content listing
```

Can reproduce on overlayfs machine with:

```
DOCKER_GRAPHDRIVER=overlay make test-integration-cli
```
