[ONOS-2613] Unit test the BGP Update message(LinkStateAttribute)

Change-Id: Id9545296612bed858459c8386368c66cb2159173
diff --git a/protocols/bgp/bgpio/src/main/java/org/onosproject/bgpio/protocol/ver4/BgpPathAttributes.java b/protocols/bgp/bgpio/src/main/java/org/onosproject/bgpio/protocol/ver4/BgpPathAttributes.java
index 13e52ca..7189ef6 100644
--- a/protocols/bgp/bgpio/src/main/java/org/onosproject/bgpio/protocol/ver4/BgpPathAttributes.java
+++ b/protocols/bgp/bgpio/src/main/java/org/onosproject/bgpio/protocol/ver4/BgpPathAttributes.java
@@ -24,6 +24,7 @@
 import org.onosproject.bgpio.types.AsPath;
 import org.onosproject.bgpio.types.BgpErrorType;
 import org.onosproject.bgpio.types.BgpValueType;
+import org.onosproject.bgpio.types.LinkStateAttributes;
 import org.onosproject.bgpio.types.LocalPref;
 import org.onosproject.bgpio.types.Med;
 import org.onosproject.bgpio.types.NextHop;
@@ -54,7 +55,7 @@
     */
     protected static final Logger log = LoggerFactory.getLogger(BgpPathAttributes.class);
 
-    public static final int LINK_STATE_ATTRIBUTE_TYPE = 50;
+    public static final int LINK_STATE_ATTRIBUTE_TYPE = 29;
     public static final int MPREACHNLRI_TYPE = 14;
     public static final int MPUNREACHNLRI_TYPE = 15;
 
@@ -139,7 +140,7 @@
                         .isMpUnReachNlriSet();
                 break;
             case LINK_STATE_ATTRIBUTE_TYPE:
-                //TODO: To be merged later
+                pathAttribute = LinkStateAttributes.read(cb);
                 break;
             default:
                 //skip bytes for unsupported attribute types