backports: add napi_gro_flush()

napi_gro_flush() got a second argument in kernel 3.7, but it
can be ignored for prior kernel versions.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
diff --git a/backport/backport-include/linux/netdevice.h b/backport/backport-include/linux/netdevice.h
index f77e3eb..a39bff7 100644
--- a/backport/backport-include/linux/netdevice.h
+++ b/backport/backport-include/linux/netdevice.h
@@ -521,6 +521,7 @@
 #define netdev_notify_peers(dev)
 #elif LINUX_VERSION_CODE < KERNEL_VERSION(3,7,0)
 #define netdev_notify_peers(dev) netif_notify_peers(dev)
+#define napi_gro_flush(napi, old) napi_gro_flush(napi)
 #endif
 
 #endif /* __BACKPORT_NETDEVICE_H */