setup module: Additional facts when using ansible with Linux on System z

- Improved parsing of /proc/cpuinfo to take the specifics of Linux on System z. ansible_processor and ansible_processor_cores are now completed.
- Also improved virtualization facts in the same environment, parsing the output of /usr/bin/lscpu to populate virtualization_type and virtualization_role more precisely. If lscpu is not available, then stick to the previous behavior.