[service] system service also needs d-bus now

TODO: this dependency will be removed when there will be "fake" services
for providers to require provider-related services and to be started
before statefs

Signed-off-by: Denis Zalevskiy <denis.zalevskiy@jolla.com>
[lib] soname for libraries

Signed-off-by: Denis Zalevskiy <denis.zalevskiy@jolla.com>