ceph-rgw-loadbalancer: Fix SSL newline issue

ceph-rgw-loadbalancer: Fix SSL newline issue

The ad7a5da commit introduced a regression when using TLS on haproxy
via the haproxy_frontend_ssl_certificate variable.
This cause the "stats socket" and the "tune.ssl.default-dh-param"
parameters to be on the same line resulting haproxy failing to start.

[ALERT] 351/140240 (21388) : parsing [xxxxx] : 'stats socket' : unknown
keyword 'tune.ssl.default-dh-param'. Registered
[ALERT] 351/140240 (21388) : Fatal errors found in configuration.

Fixes: #4869
Signed-off-by: Florian Faltermeier <florian.faltermeier@uibk.ac.at>
(cherry picked from commit 9d081e2453285599b78ade93ff9617a28b3d1f02)