Minor improvement dealing with Port

- include annotations in DefaultPort#toString()
- add method to retrieve a Port using ConnectPoint

Change-Id: I75f24e53235f46fa8deeb62b55bec2ecafae907c
diff --git a/core/api/src/main/java/org/onosproject/net/DefaultPort.java b/core/api/src/main/java/org/onosproject/net/DefaultPort.java
index 85e2de1..70023cc 100644
--- a/core/api/src/main/java/org/onosproject/net/DefaultPort.java
+++ b/core/api/src/main/java/org/onosproject/net/DefaultPort.java
@@ -121,6 +121,7 @@
                 .add("isEnabled", isEnabled)
                 .add("type", type)
                 .add("portSpeed", portSpeed)
+                .add("annotations", annotations())
                 .toString();
     }
 
diff --git a/core/api/src/main/java/org/onosproject/net/device/DeviceService.java b/core/api/src/main/java/org/onosproject/net/device/DeviceService.java
index ce988c5..290f7d7 100644
--- a/core/api/src/main/java/org/onosproject/net/device/DeviceService.java
+++ b/core/api/src/main/java/org/onosproject/net/device/DeviceService.java
@@ -16,6 +16,7 @@
 package org.onosproject.net.device;
 
 import org.onosproject.event.ListenerService;
+import org.onosproject.net.ConnectPoint;
 import org.onosproject.net.Device;
 import org.onosproject.net.DeviceId;
 import org.onosproject.net.MastershipRole;
@@ -144,6 +145,16 @@
     Port getPort(DeviceId deviceId, PortNumber portNumber);
 
     /**
+     * Returns the port with the specified connect point.
+     *
+     * @param cp connect point
+     * @return device port
+     */
+    default Port getPort(ConnectPoint cp) {
+        return getPort(cp.deviceId(), cp.port());
+    }
+
+    /**
      * Indicates whether or not the device is presently online and available.
      * Availability, unlike reachability, denotes whether ANY node in the
      * cluster can discover that this device is in an operational state,