Adds receive side scaling (RSS) support to distribute
pkts/flows across multiple queues. Sets up key, indirection
table etc. Also added extraction of HW calculated rxhash and
adding to same to SKB ie NETIF_F_RXHASH offload support.

Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>