[NET]: Turn nfmark into generic mark

nfmark is being used in various subsystems and has become
the defacto mark field for all kinds of packets. Therefore
it makes sense to rename it to `mark' and remove the
dependency on CONFIG_NETFILTER.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index fc195a4..23633bf 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -386,6 +386,7 @@
 	dst_release(to->dst);
 	to->dst = dst_clone(from->dst);
 	to->dev = from->dev;
+	to->mark = from->mark;
 
 	/* Copy the flags to each fragment. */
 	IPCB(to)->flags = IPCB(from)->flags;
@@ -394,7 +395,6 @@
 	to->tc_index = from->tc_index;
 #endif
 #ifdef CONFIG_NETFILTER
-	to->nfmark = from->nfmark;
 	/* Connection association is same as pre-frag packet */
 	nf_conntrack_put(to->nfct);
 	to->nfct = from->nfct;