Fix reference comparison of object

- fixes ONOS-6023

Change-Id: I24e58b46d0c7cd65e55ecc0e54f76c5cb7ff649c
(cherry picked from commit f92598be5d4b833d7264ce46056bef6936b5b59d)
diff --git a/core/net/src/main/java/org/onosproject/net/link/impl/BasicLinkOperator.java b/core/net/src/main/java/org/onosproject/net/link/impl/BasicLinkOperator.java
index 1027f75..31820a9 100644
--- a/core/net/src/main/java/org/onosproject/net/link/impl/BasicLinkOperator.java
+++ b/core/net/src/main/java/org/onosproject/net/link/impl/BasicLinkOperator.java
@@ -81,7 +81,7 @@
         if (cfg.metric() != DEF_METRIC) {
             b.set(AnnotationKeys.METRIC, String.valueOf(cfg.metric()));
         }
-        if (cfg.latency() != DEF_DURATION) {
+        if (!cfg.latency().equals(DEF_DURATION)) {
             b.set(AnnotationKeys.LATENCY, cfg.latency().toString());
         }
         if (cfg.bandwidth() != DEF_BANDWIDTH) {