Add Optional match fields support to PI subsystem

Change-Id: Ic458f59cab98340e40c04a0ad060d3c725ac5dbb
diff --git a/core/common/src/test/resources/org/onosproject/codec/impl/PiCriterion.json b/core/common/src/test/resources/org/onosproject/codec/impl/PiCriterion.json
index d1df49e..6635641 100644
--- a/core/common/src/test/resources/org/onosproject/codec/impl/PiCriterion.json
+++ b/core/common/src/test/resources/org/onosproject/codec/impl/PiCriterion.json
@@ -23,6 +23,11 @@
             "match": "range",
             "highValue": "20",
             "lowValue": "10"
+        },
+        {
+            "field": "eth_dst",
+            "match": "optional",
+            "value": "001122334455"
         }
     ]
 }