[IPV4]: reset IPCB flags when neccessary

Reset IPSKB_XFRM_TUNNEL_SIZE flags in ipip and ip_gre hard_start_xmit
function before the packet reenters IP. This is neccessary so the
encapsulated packets are checked not to be oversized in xfrm4_output.c
again. Reset all flags in sit when a packet changes its address family.

Also remove some obsolete IPSKB flags.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ip.h b/include/net/ip.h
index 7bb5804..52f4d9c 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -37,11 +37,9 @@
 	struct ip_options	opt;		/* Compiled IP options		*/
 	unsigned char		flags;
 
-#define IPSKB_MASQUERADED	1
-#define IPSKB_TRANSLATED	2
-#define IPSKB_FORWARDED		4
-#define IPSKB_XFRM_TUNNEL_SIZE	8
-#define IPSKB_FRAG_COMPLETE	16
+#define IPSKB_FORWARDED		1
+#define IPSKB_XFRM_TUNNEL_SIZE	2
+#define IPSKB_FRAG_COMPLETE	4
 };
 
 struct ipcm_cookie