ONOS-1746 Fixed hashCode implementation to be immune from non-deterministic enum hashCode.

Change-Id: I96d0a7850ee28d62b1152c4fee4f4ce7648c4931
diff --git a/core/api/src/main/java/org/onosproject/net/flow/criteria/MetadataCriterion.java b/core/api/src/main/java/org/onosproject/net/flow/criteria/MetadataCriterion.java
index 9957840..8177b48 100644
--- a/core/api/src/main/java/org/onosproject/net/flow/criteria/MetadataCriterion.java
+++ b/core/api/src/main/java/org/onosproject/net/flow/criteria/MetadataCriterion.java
@@ -57,7 +57,7 @@
 
     @Override
     public int hashCode() {
-        return Objects.hash(type(), metadata);
+        return Objects.hash(type().ordinal(), metadata);
     }
 
     @Override