[QNX] Unable to create CMake project targetting QNX

Simple Qt Quick project is created using CMake build for QNX 7.0 kit.

Configuration fails with following output:

cc: unknown option: '--sysroot

This can be 'fixed' by unsetting SYSROOT option like this: 

cmake . -DCMAKE_SYSROOT:STRING=

Unfortunately then the next issue pops up: 

No known features for CXX compiler "QCC"

As a user I'd like to see the project configure and build without me modifying the toolchain files or QTCreator. Is it possible to fix this in QTCreator?

This issue is related to:  #QTCREATORBUG-20386