* The supported architectures are inside the config now
* Symlinks get created for that list of supported architectures now.
* During initialization, the architecture from the selected device
gets checked against the list of supported architectures. When
it is not included, a meaningful exception gets raised.
* the aportgen and (cross-compiler) build tests make use of the
new variable now (they had armhf and aarch64 hardcoded previously).