Also add pvcalls-back to the Makefile.
Signed-off-by: NStefano Stabellini <stefano@aporeto.com>
Reviewed-by: NJuergen Gross <jgross@suse.com>
CC: boris.ostrovsky@oracle.com
CC: jgross@suse.com
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>