rabbitmq-server depends on os-svc-install

Since commit 7352f49f2e0b66d7da81ac5f943c59ef301c37c2, the
rabbitmq-server element has made use of os-svc-enable, which
is part of the os-svc-install element.

Change-Id: I335f2730e84c346b290432518db25167867b0eca
Merge "rabbitmq-server depends on os-svc-install"