Qnx: Show the .pro file when adding bar-descriptor to project

Task-number: QTCREATORBUG-11300

Change-Id: If064d79c35d95b1ea1c5124be60d22d2ffee93f4
Reviewed-by: David Kaspar <dkaspar@blackberry.com>
Reviewed-by: Tobias Nätterlund <tobias.naetterlund@kdab.com>
Reviewed-by: Nicolas Arnaud-Cormos <nicolas@kdab.com>