Exception handling around kafka produce()

Change-Id: I8d87b4b5363442477238484b58783f4c452c4bbd
diff --git a/voltha/adapters/openolt/openolt_kafka_proxy.py b/voltha/adapters/openolt/openolt_kafka_proxy.py
index 1541bd9..0d3a79a 100644
--- a/voltha/adapters/openolt/openolt_kafka_proxy.py
+++ b/voltha/adapters/openolt/openolt_kafka_proxy.py
@@ -64,7 +64,10 @@
         self.kproducer = Producer(**conf)
 
     def send_message(self, topic, msg, key=None):
-        self.kproducer.produce(topic, msg)
+        try:
+            self.kproducer.produce(topic, msg)
+        except BufferError:
+            log.error('Local producer queue is full')
 
     def is_faulty(self):
         return self.faulty