Avoid warning when seeing VLAN_POP in next treatment

Change-Id: Id4b63842be30afc1689aef7392a6b9b0d2e922ae
diff --git a/pipelines/fabric/src/main/java/org/onosproject/pipelines/fabric/FabricTreatmentInterpreter.java b/pipelines/fabric/src/main/java/org/onosproject/pipelines/fabric/FabricTreatmentInterpreter.java
index ca00687..e5d11a5 100644
--- a/pipelines/fabric/src/main/java/org/onosproject/pipelines/fabric/FabricTreatmentInterpreter.java
+++ b/pipelines/fabric/src/main/java/org/onosproject/pipelines/fabric/FabricTreatmentInterpreter.java
@@ -214,6 +214,9 @@
                         case MPLS_LABEL:
                             modMplsInst = (ModMplsLabelInstruction) l2Inst;
                             break;
+                        case VLAN_POP:
+                            // VLAN_POP will be handled by mapEgressNextTreatment()
+                            break;
                         default:
                             log.warn("Unsupported l2 instruction sub type {} [table={}, {}]",
                                      l2Inst.subtype(), tableId, treatment);