Make nodeGetInfo report the correct number of NUMA nodes.

Make nodeGetInfo report the correct number of NUMA nodes.

The nodeGetInfo code was always assuming that machine had a
single NUMA node, which is not correct.  The good news is that
libnuma gives us this information pretty easily, so let's
properly report it.

NOTE: With recent hardware starting to support CPU hot-add
and hot-remove, both this code and the nodeCapsInitNUMA()
code are quickly going to become obsolete.  We'll have to
think of a more dynamic solution for dealing with NUMA
nodes and CPUs that can come and go at will.

Signed-off-by: Chris Lalancette <clalance@redhat.com>