The virNodeParseSocket() function tries to get socked ID from
'topology/physical_package_id' file. However, on some architectures
the file contains the -1 constant which makes in turn libvirt think
the info extraction was unsuccessful. If that's the case, we need to
overwrite the obtained integer with zero like we are doing for other
architectures.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>