lscpu: use hypervisor generated topology information

lscpu: use hypervisor generated topology information

The readable output prints also informations like cores per socket etc.
On newer kernel versions on s390 this information is available via
/proc/sysinfo. However it does not contain the layout of the guest but
the layout of the real machine.
Nevertheless this is better than random guessing with completely broken
numbers like we have it now on s390. If the information is not available
we fall back to old mechanism with more or less random numbers.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>