virtio-net: Introduce RSS receive steering feature

virtio-net: Introduce RSS receive steering feature

RSS (Receive-side scaling) defines hash calculation
rules and decision on receive virtqueue according to
the calculated hash, provided mask to apply and
provided indirection table containing indices of
receive virqueues. The driver sends the control
command to enable multiqueue and provide parameters
for receive steering.

Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Link: https://lore.kernel.org/r/20200302115003.14877-3-yuri.benditovich@daynix.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>