QNX: Handle Qt::WindowDoesNotAcceptFocus correctly.

Discovered while working on:
Task-number: QTBUG-32385

Change-Id: Id1ff31ea6a367983676125810b4f49629233d374
Reviewed-by: Andreas Holzammer <andreas.holzammer@kdab.com>
Reviewed-by: Frank Osterfeld <frank.osterfeld@kdab.com>
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>