Merge branch 'inet_csums'

Tom Herbert says:

====================
net: Support checksum in UDP

This patch series adds support for using checksums in UDP tunnels. With
this it is possible that two or more checksums may be set within the
same packet and we would like to do that efficiently.

This series also creates some new helper functions to be used by various
tunnel protocol implementations.

v2: Fixed indentation in tcp_v6_send_check arguments.
v3: Move udp_set_csum and udp6_set_csum to be not inlined
    Also have this functions call with a nocheck boolean argument
    instead of passing a sock structure.
====================

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