VOL-406 add logging configuration to swarm stack files

Change-Id: I6e75649c6f1cef3948437e59c778c562c828badc
(cherry picked from commit 4e920b7e69587ac2395f4069bfa5ed298bbeb2c5)
diff --git a/compose/docker-compose-voltha-swarm.yml b/compose/docker-compose-voltha-swarm.yml
index 7826e39..bff9f90 100644
--- a/compose/docker-compose-voltha-swarm.yml
+++ b/compose/docker-compose-voltha-swarm.yml
@@ -2,6 +2,11 @@
 services:
   vcore:
     image: cord/voltha:latest
+    logging:
+      driver: "json-file"
+      options:
+        max-size: "10m"
+        max-file: 3
     deploy:
       replicas: 3
     entrypoint: