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/wimax/op-msg.c b/net/wimax/op-msg.c
index d5b7c37..0694d62 100644
--- a/net/wimax/op-msg.c
+++ b/net/wimax/op-msg.c
@@ -77,6 +77,7 @@
 #include <linux/netdevice.h>
 #include <linux/wimax.h>
 #include <linux/security.h>
+#include <linux/export.h>
 #include "wimax-internal.h"