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/core/net-traces.c b/net/core/net-traces.c
index 52380b1..ba3c012 100644
--- a/net/core/net-traces.c
+++ b/net/core/net-traces.c
@@ -11,6 +11,7 @@
 #include <linux/inetdevice.h>
 #include <linux/inet.h>
 #include <linux/interrupt.h>
+#include <linux/export.h>
 #include <linux/netpoll.h>
 #include <linux/sched.h>
 #include <linux/delay.h>