[NET]: Added GSO toggle

This patch adds a generic segmentation offload toggle that can be turned
on/off for each net device.  For now it only supports in TCPv4.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index cf2abec..c6310ae 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -411,6 +411,8 @@
 #define ETHTOOL_GPERMADDR	0x00000020 /* Get permanent hardware address */
 #define ETHTOOL_GUFO		0x00000021 /* Get UFO enable (ethtool_value) */
 #define ETHTOOL_SUFO		0x00000022 /* Set UFO enable (ethtool_value) */
+#define ETHTOOL_GGSO		0x00000023 /* Get GSO enable (ethtool_value) */
+#define ETHTOOL_SGSO		0x00000024 /* Set GSO enable (ethtool_value) */
 
 /* compatibility with older code */
 #define SPARC_ETH_GSET		ETHTOOL_GSET