Remove ERROR log that happens during normal processing

Change-Id: I968868875fd903e328dc7dd15e537ff3d8295254
diff --git a/utils/misc/src/main/java/org/onlab/packet/ONOSLLDP.java b/utils/misc/src/main/java/org/onlab/packet/ONOSLLDP.java
index 7405bbf..9b379f6 100644
--- a/utils/misc/src/main/java/org/onlab/packet/ONOSLLDP.java
+++ b/utils/misc/src/main/java/org/onlab/packet/ONOSLLDP.java
@@ -307,7 +307,6 @@
         if (type == PORT_TLV_INTERFACE_NAME_SUBTYPE) {
             return new String(portBB.array(), portBB.position(), portBB.remaining(), StandardCharsets.UTF_8);
         } else {
-            log.error("Cannot find the port name tlv type.");
             return null;
         }
     }