rabbitmq is started three times:
1st time in rabbitmq_install with default config
2nd time in rabbitmq_set_cookie with default config
3rd time in rabbitmq_post_install with OSA config
however, there is no need for that and we can remove the 1st one and
the 2nd as it uses a default config which might break deployments
(e.g. if number of threads is limited through cgroups)
Change-Id: Iaef3b91d2a555bf0681f4a7d018d6d93e93889b4
Signed-off-by: Manuel Buil <mbuil@suse.com>