Added alarm suppression methods

Change-Id: I0975060bae22686de19ddf55896ff860ff4f797a
diff --git a/voltha/adapters/adtran_olt/adtran_olt.py b/voltha/adapters/adtran_olt/adtran_olt.py
index c5ae568..dc18e11 100644
--- a/voltha/adapters/adtran_olt/adtran_olt.py
+++ b/voltha/adapters/adtran_olt/adtran_olt.py
@@ -309,3 +309,11 @@
         """
         log.info('rx_inter_adapter_msg')
         raise NotImplementedError()
+
+    def suppress_alarm(self, filter):
+        log.info('suppress_alarm', filter=filter)
+        raise NotImplementedError()
+
+    def unsuppress_alarm(self, filter):
+        log.info('unsuppress_alarm', filter=filter)
+        raise NotImplementedError()