Qnx: Remove BlackBerry Gui templates

The BlackBerry Gui templates are only adding BlackBerry 10 style
which can be done with a standard Qt Gui Application.

Task-number: QTCREATORBUG-10242

Change-Id: Iba29088acc1720318f09138688dd4eae544338a4
Reviewed-by: Nicolas Arnaud-Cormos <nicolas@kdab.com>