RDS: Export symbols from core RDS

Now that rdma and tcp transports will be modularized,
we need to export a number of functions so they can call them.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/rds/cong.c b/net/rds/cong.c
index 710e459..dd2711d 100644
--- a/net/rds/cong.c
+++ b/net/rds/cong.c
@@ -254,6 +254,7 @@
 		read_unlock_irqrestore(&rds_cong_monitor_lock, flags);
 	}
 }
+EXPORT_SYMBOL_GPL(rds_cong_map_updated);
 
 int rds_cong_updated_since(unsigned long *recent)
 {