Refactored LLDP link discovery to be shared by multiple providers

Change-Id: Ia2253ff6bb39186e936ddbaff0c416aa5be6e117
diff --git a/providers/lldp/src/test/java/org/onosproject/provider/lldp/impl/LldpLinkProviderTest.java b/providers/lldp/src/test/java/org/onosproject/provider/lldp/impl/LldpLinkProviderTest.java
index 20d615a..8b47f44 100644
--- a/providers/lldp/src/test/java/org/onosproject/provider/lldp/impl/LldpLinkProviderTest.java
+++ b/providers/lldp/src/test/java/org/onosproject/provider/lldp/impl/LldpLinkProviderTest.java
@@ -76,6 +76,7 @@
 import org.onosproject.net.packet.PacketProcessor;
 import org.onosproject.net.packet.PacketServiceAdapter;
 import org.onosproject.net.provider.ProviderId;
+import org.onosproject.provider.lldpcommon.LinkDiscovery;
 
 import com.google.common.collect.ArrayListMultimap;
 import com.google.common.collect.ImmutableList;