[TCP]: Move the tcp sock states to net/tcp_states.h

Lots of places just needs the states, not even linux/tcp.h, where this
enum was, needs it.

This speeds up development of the refactorings as less sources are
rebuilt when things get moved from net/tcp.h.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/decnet/dn_nsp_in.c b/net/decnet/dn_nsp_in.c
index 202dbde..369f25b 100644
--- a/net/decnet/dn_nsp_in.c
+++ b/net/decnet/dn_nsp_in.c
@@ -60,7 +60,7 @@
 #include <linux/inet.h>
 #include <linux/route.h>
 #include <net/sock.h>
-#include <net/tcp.h>
+#include <net/tcp_states.h>
 #include <asm/system.h>
 #include <linux/fcntl.h>
 #include <linux/mm.h>