core: more accurate cores(threads) ui representation

in case of 2 cores 2 sockets and cluster-count threads as cores, we want
to show at the host general tab
2(4) which reads 2 cores which is actual 4 for scheduling.

without that fixed it showed the overall count which was 2(8)

Change-Id: I4a2c3563bfd667331a58bf558c1161d4e379c624
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1169404
Signed-off-by: Roy Golan <rgolan@redhat.com>