Merge branch 'vxlan_gso_check'

Joe Stringer says:

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Implement ndo_gso_check() for vxlan nics

Most NICs that report NETIF_F_GSO_UDP_TUNNEL support VXLAN, and not other
UDP-based encapsulation protocols where the format and size of the header may
differ. This patch series implements a generic ndo_gso_check() for detecting
VXLAN, then reuses it for these NICs.

Implementation shamelessly stolen from Tom Herbert (with minor fixups):
http://thread.gmane.org/gmane.linux.network/332428/focus=333111

v2: Drop i40e/fm10k patches (code diverged; handling separately).
    Refactor common code into vxlan_gso_check() helper.
    Minor style fixes.
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Signed-off-by: David S. Miller <davem@davemloft.net>