Port qtqa to CMake

Here are the parts I've identified that Coin is using from qtqa.

License checking which is executed only for configs marked with the LicenseCheck feature.

This is separate from Build and Test phases (LicenseCheck phase), but still appears under Tests in Coin logs. We can probably implement it using instructions inspired by
https://codereview.qt-project.org/c/qt/qtbase/+/271207/59/coin/instructions/execute_license_check.yaml

Binary compatibility tests, which are executed only for Linux configurations, as part of the general testing instructions of a module.
Instructions can be inspired by
https://codereview.qt-project.org/c/qt/qtbase/+/271207/59/coin/instructions/execute_bic_tests.yaml

In this BiC mode, the qtqa repo is downloaded, an environment variable is set like

QT_MODULE_TO_TEST=/home/qt/work/qt/qtsvg

and qmake is ran directly on the

/home/qt/work/qt/qtqa-latest/tests/postbuild/bic

subfolder, after which make check is run (which implicitly builds the test). The BiC test expects to find qmake in PATH, and uses QStandardPaths::findExecutable() to actually find it.

We should consider in the future whether the test needs to call cmake instead of qmake, and how things should be inter-connected in that case.

Finally, qtqa is only built with a Windows 7 MinGW configuration in dev (when the repo itself is built in Coin), and build phase basically does nothing, and test phase builds the tests, but doesn't run them.

This is hardcoded in modules_qt5.py of Coin repo. Build phase is a regular qmake build phase. The test phase contains instructions to configure and build using qmake and run "make check" for the "tests" and "scripts" subfolders.