New test adds 14 to the unknown value before adding to the packet pointer,
 meaning there's no 'fixed offset' field and instead we add into the
 var_off, yielding a '4n+2' value.
Signed-off-by: NEdward Cree <ecree@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>