fsl/fman: include IPSEC SPI in the Keygen extraction

The keygen extracted fields are used as input for the hash that
determines the incoming frames distribution. Adding IPSEC SPI so
different IPSEC flows can be distributed to different CPUs.

Signed-off-by: Madalin Bucur <madalin.bucur@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>