Mechanism to add Port annotation via netcfg

- intended to be used for driver to support ONOS-5895

Change-Id: Iddcf6f1b99273e8f8670b5f64fc9831e5f4ce3cd
diff --git a/core/net/src/main/java/org/onosproject/net/config/impl/BasicNetworkConfigs.java b/core/net/src/main/java/org/onosproject/net/config/impl/BasicNetworkConfigs.java
index 0bd8b91..5cabfbd 100644
--- a/core/net/src/main/java/org/onosproject/net/config/impl/BasicNetworkConfigs.java
+++ b/core/net/src/main/java/org/onosproject/net/config/impl/BasicNetworkConfigs.java
@@ -36,6 +36,7 @@
 import org.onosproject.net.config.basics.BasicLinkConfig;
 import org.onosproject.net.config.basics.BasicRegionConfig;
 import org.onosproject.net.config.basics.BasicUiTopoLayoutConfig;
+import org.onosproject.net.config.basics.PortAnnotationConfig;
 import org.onosproject.net.config.basics.SubjectFactories;
 import org.onosproject.net.region.RegionId;
 import org.onosproject.ui.model.topo.UiTopoLayoutId;
@@ -112,6 +113,14 @@
                 public BasicUiTopoLayoutConfig createConfig() {
                     return new BasicUiTopoLayoutConfig();
                 }
+            },
+            new ConfigFactory<ConnectPoint, PortAnnotationConfig>(CONNECT_POINT_SUBJECT_FACTORY,
+                    PortAnnotationConfig.class,
+                    PortAnnotationConfig.CONFIG_KEY) {
+                @Override
+                public PortAnnotationConfig createConfig() {
+                    return new PortAnnotationConfig();
+                }
             }
     );