rib: fix incorrect operator<< output

refs #3423

Change-Id: I22137a1ad2c3b64d74b7ba2fe6b5f7f55486c276
diff --git a/rib/rib.cpp b/rib/rib.cpp
index 97492b2..422de9f 100644
--- a/rib/rib.cpp
+++ b/rib/rib.cpp
@@ -507,7 +507,7 @@
 operator<<(std::ostream& os, const Rib& rib)
 {
   for (const auto& item : rib) {
-    os << item.second << "\n";
+    os << *item.second << "\n";
   }
 
   return os;