Qnx: Fixing BarDescriptorEditor to open as unmodifed

Task-number: QTCREATORBUG-10228

Change-Id: I0660619b3279ff4889091c19622a98771c213a3e
Reviewed-by: David Kaspar <dkaspar@blackberry.com>
Reviewed-by: Tobias Nätterlund <tobias.naetterlund@kdab.com>
Reviewed-by: Mehdi Fekari <mfekari@blackberry.com>
Reviewed-by: Nicolas Arnaud-Cormos <nicolas@kdab.com>