ip_tunnel: Add dont fragment flag.

This flag will be used by ovs tunneling.
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/ip_tunnels.h

@@ -73,6 +73,7 @@ struct ip_tunnel {
 #define TUNNEL_REC	__cpu_to_be16(0x20)
 #define TUNNEL_VERSION	__cpu_to_be16(0x40)
 #define TUNNEL_NO_KEY	__cpu_to_be16(0x80)
+#define TUNNEL_DONT_FRAGMENT    __cpu_to_be16(0x0100)
 
 struct tnl_ptk_info {
 	__be16 flags;