net: sxgbe: add Checksum offload support for Samsung sxgbe

This patch adds TX and RX checksum offload support.

Signed-off-by: Vipul Pandya <vipul.pandya@samsung.com>
Neatening-by: Joe Perches <joe@perches.com>
Signed-off-by: Byungho An <bh74.an@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc drivers/net/ethernet/samsung/sxgbe/sxgbe_common.h
Simple merge

diff --cc drivers/net/ethernet/samsung/sxgbe/sxgbe_core.c
Simple merge

diff --cc drivers/net/ethernet/samsung/sxgbe/sxgbe_desc.h
Simple merge

diff --cc drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
Simple merge