Revise supported architectures, operatingsystems and buildtargets
Check and define what architectures, operatingsystems and buildtargets we want:
- amd64, i386, aarch64, s390x, ...?
- Debian 12(stable), Debian(11), Ubuntu ?!?!?!?!, RedHatDerivate>9000 ??!?!?!, ...?
- GCC 2.9, clang xxx, intel-who-knows-what, ...?
- ....
Should optimally be done before Icecast 2.5 rc1