virsh: fix vcpupin info

virsh: fix vcpupin info

The "virDomainGetInfo" will get for running domain only live info and for
offline domain only config info. There was no way how to get config info
for running domain. We will use "vshCPUCountCollect" instead to get the
correct cpu count that we need to pass to "virDomainGetVcpuPinInfo".

Also cleanup some unnecessary variables and checks that are done by
drivers.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1160559

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>