loadbalancer: fix Redis timeout HAproxy config

loadbalancer: fix Redis timeout HAproxy config

Current HAproxy config is broken for Redis timeout parameters. This is what we
have today by default in HAproxy logs:
[WARNING] 238/115010 (13878) : config : missing timeouts for proxy 'redis'.
| While not properly invalid, you will certainly encounter various problems
| with such a configuration. To fix this, please ensure that all following
| timeouts are set to a non-zero value: 'client', 'connect', 'server'.

This patch removes the explicit setting of client and server timeouts to 0,
which is the cause of the above warning.  Instead, Redis will simply inherit the
haproxy defaults, which should be a more reasonable setting, and result in no
warnings.

Change-Id: Ibe7941bec02f5facf21732910c9ad96f547ff8e5