Make DiscreteResourceCodecs package private

Change-Id: I4db1440729ce78e4fd64d3fe43e942f6d39e779c
(cherry picked from commit 078b6b819d56d949b206037aedac56d9eb596611)
diff --git a/core/store/dist/src/main/java/org/onosproject/store/resource/impl/MplsCodec.java b/core/store/dist/src/main/java/org/onosproject/store/resource/impl/MplsCodec.java
index bc741e5..ce5972e 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/resource/impl/MplsCodec.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/resource/impl/MplsCodec.java
@@ -23,7 +23,7 @@
  * Codec for MplsLabel.
  */
 @Beta
-public final class MplsCodec implements DiscreteResourceCodec<MplsLabel> {
+final class MplsCodec implements DiscreteResourceCodec<MplsLabel> {
     @Override
     public int encode(MplsLabel resource) {
         return resource.toInt();
diff --git a/core/store/dist/src/main/java/org/onosproject/store/resource/impl/VlanCodec.java b/core/store/dist/src/main/java/org/onosproject/store/resource/impl/VlanCodec.java
index 270645a..f6a34c1 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/resource/impl/VlanCodec.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/resource/impl/VlanCodec.java
@@ -23,7 +23,7 @@
  * Codec for Vlan.
  */
 @Beta
-public final class VlanCodec implements DiscreteResourceCodec<VlanId> {
+final class VlanCodec implements DiscreteResourceCodec<VlanId> {
     @Override
     public int encode(VlanId resource) {
         return resource.toShort();