Updated P4_16 sample programs to reflect HW testbed

Change-Id: I9d76c9bc7632760cd9af1a3a431856291903eaf9
diff --git a/core/net/src/test/java/org/onosproject/net/pi/impl/MockInterpreter.java b/core/net/src/test/java/org/onosproject/net/pi/impl/MockInterpreter.java
index 2dff2f1..794e7f8 100644
--- a/core/net/src/test/java/org/onosproject/net/pi/impl/MockInterpreter.java
+++ b/core/net/src/test/java/org/onosproject/net/pi/impl/MockInterpreter.java
@@ -50,7 +50,7 @@
     static final String TABLE0 = "table0";
     static final String SEND_TO_CPU = "send_to_cpu";
     static final String PORT = "port";
-    static final String DROP = "drop";
+    static final String DROP = "_drop";
     static final String SET_EGRESS_PORT = "set_egress_port";
 
     static final PiHeaderFieldId IN_PORT_ID = PiHeaderFieldId.of("standard_metadata", "ingress_port");