Reason being that it's much easier to trigger compile errors with the
QNX6.6 toolchain than with the newer QNX7, so these show up at once
and not only at qt5.git integration.

Task-number: QTBUG-62047
Change-Id: Ib45728c92488206dbede019e4583bc9a5386b90f
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>