adding break statements that were missing

Change-Id: I59108b923f73d0e6925b73574f5d4cdb5a18777d
diff --git a/providers/openflow/flow/src/main/java/org/onlab/onos/provider/of/flow/impl/FlowModBuilder.java b/providers/openflow/flow/src/main/java/org/onlab/onos/provider/of/flow/impl/FlowModBuilder.java
index 8c009a7..dd5e8bf 100644
--- a/providers/openflow/flow/src/main/java/org/onlab/onos/provider/of/flow/impl/FlowModBuilder.java
+++ b/providers/openflow/flow/src/main/java/org/onlab/onos/provider/of/flow/impl/FlowModBuilder.java
@@ -115,8 +115,10 @@
                 return new LinkedList<>();
             case L2MODIFICATION:
                 acts.add(buildL2Modification(i));
+                break;
             case L3MODIFICATION:
                 acts.add(buildL3Modification(i));
+                break;
             case OUTPUT:
                 OutputInstruction out = (OutputInstruction) i;
                 acts.add(factory.actions().buildOutput().setPort(