[VOL-4548] openonuAdapterGo - memory leak seen in long term tests

Change-Id: I306e3b8d9529ba1ffb43f93cd70524931d7c5e3c
diff --git a/internal/pkg/onuadaptercore/uniportadmin.go b/internal/pkg/onuadaptercore/uniportadmin.go
index 4b829d5..090e2fe 100644
--- a/internal/pkg/onuadaptercore/uniportadmin.go
+++ b/internal/pkg/onuadaptercore/uniportadmin.go
@@ -531,3 +531,10 @@
 		return fmt.Errorf("lockStateFsm uni-set responseError for device-id %s", oFsm.deviceID)
 	}
 }
+
+// PrepareForGarbageCollection - remove references to prepare for garbage collection
+func (oFsm *lockStateFsm) PrepareForGarbageCollection(ctx context.Context, aDeviceID string) {
+	logger.Debugw(ctx, "prepare for garbage collection", log.Fields{"device-id": aDeviceID})
+	oFsm.pDeviceHandler = nil
+	oFsm.pOmciCC = nil
+}