ixgbe: add VXLAN offload support for X550 devices

Add support VXLAN receive checksum offload in X550 hardware.

Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --cc drivers/net/ethernet/intel/Kconfig
Simple merge

diff --cc drivers/net/ethernet/intel/ixgbe/ixgbe.h
Simple merge

diff --cc drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
Simple merge

diff --cc drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
Simple merge