Fix Enginio archive names in installer configs

Application build script outputs the application archives names in
format:

qt5_<appname>.7z

E.g. for Enginio it will become: qt5_qtenginio.7z

Change-Id: I754ad92affde3f0c784a7bd373959099e52b7744
Reviewed-by: Sergio Ahumada <sergio.ahumada@digia.com>