haproxy: write to container log files

This moves the haproxy containers to syslog with tags that will get
each container's output filtered into /var/log/containers.

Change-Id: I65294baec3c092ede5ee97856d8d879174b0d8d4

playbooks/roles/haproxy/files/docker/docker-compose.yaml

@@ -11,6 +11,10 @@ services:
       - /dev/log:/dev/log
       - /var/haproxy/etc:/usr/local/etc/haproxy
       - /var/haproxy/run:/var/haproxy/run
+    logging:
+      driver: syslog
+      options:
+        tag: "docker-haproxy"
   haproxy-statsd:
     restart: always
     image: docker.io/opendevorg/haproxy-statsd:latest
@@ -20,3 +24,7 @@ services:
     environment:
       STATSD_HOST: graphite.opendev.org
       STATSD_PORT: 8125
+    logging:
+      driver: syslog
+      options:
+        tag: "docker-haproxy-statsd"