Merge branch 'xen-netback-control-ring'

Paul Durrant says:

====================
xen-netback: support for control ring

My recent patch to import an up-to-date include/xen/interface/io/netif.h
from the Xen Project brought in the necessary definitions to support the
new control shared ring and protocol. This patch series updates xen-netback
to support the new ring.

Patch #1 adds the necessary boilerplate to map the control ring and handle
messages. No implementation of the new protocol is included in this patch
so that it can be kept to a reasonable size.

Patch #2 adds the protocol implementation.

Patch #3 adds support for passing has values calculated by xen-netback to
capable frontends.

Patch #4 adds support for accepting hash values calculated by capable
frontends and using them the set the socket buffer hash.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>