ssl parameters specified on the bootstrap server are not copied to the rest

SSL parameters specified on the bootstrap server are not copied down to the volatile ones. This is causing SSL setup between MaxScale and XPAND not working properly.

Repro
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1. setup xpand cluster with ssl
3-node Xpand cluster

2. Configure maxscale with one xpand node as a server

1. cat /etc/maxscale.cnf
   [maxscale]
   log_info=1
   logdir=/data/clustrix/log
   threads=auto

[xpand1]
type=server
address=oak012white.colo.sproutsys.com
port=3306
protocol=mariadbbackend
ssl=true
ssl_cert=/etc/ssl/maxscale/server-cert.pem
ssl_key=/etc/ssl/maxscale/server-key.pem
ssl_ca=/etc/ssl/maxscale/ca-cert.pem

1. Backend specific monitor and router:
   [Backend-Monitor]
   type=monitor
   module=xpandmon
   servers=xpand1
   user=maxscale
   password=maxscale_pw
   cluster_monitor_interval=10000ms

[Read-Only-Service]
type=service
router=readconnroute
user=maxscale
password=maxscale_pw
router_options=running
cluster=Backend-Monitor

[Read-Only-Listener]
type=listener
service=Read-Only-Service
protocol=MariaDBClient
address=0.0.0.0
port=3307
authenticator=pamauth
authenticator_options=pam_backend_mapping=mariadb_passthrough
ssl=true
ssl_cert=/etc/ssl/maxscale/client-cert.pem
ssl_key=/etc/ssl/maxscale/client-key.pem
ssl_ca=/etc/ssl/maxscale/ca-cert.pem

3. start maxscale

4. show server shows ssl=true only for one xpand node, for the remaining it's ssl=false