Run both nydus and oci images with the storage plugin

It seems that we can't run an OCI image with this storage plugin directly:
```
sudo podman run -it --tls-verify=false --rm localhost:5000/ubuntu /bin/bash
Error: runc: runc create failed: unable to start container process: exec: "/bin/bash": stat /bin/bash: no such file or directory: OCI runtime attempted to invoke a command that was not found
```