Fix regression introduced in 9e8f935a while at the same time decoupling
the 'useServerStartScript' setting from whether the engine uses
requestRemoteSetup, or not.

Task-number: QTCREATORBUG-6841
Change-Id: I0850ec60e0f45ac66ba6736bcb9f75fdf73c1d23
Reviewed-by: Christian Kandeler <christian.kandeler@nokia.com>