net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c
index 6ca3574..39e02c5 100644
--- a/net/xfrm/xfrm_replay.c
+++ b/net/xfrm/xfrm_replay.c
@@ -18,6 +18,7 @@
  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+#include <linux/export.h>
 #include <net/xfrm.h>
 
 u32 xfrm_replay_seqhi(struct xfrm_state *x, __be32 net_seq)