hpux: improve hwloc_hpux_find_ldom() looking for NUMA node

hwloc_get_first_largest_obj_inside_cpuset() returns the largest/highest object,
but it could still have a child with the same cpuset.
So check children as well in case there's a matching NUMA node there.
x86: use ulong for cache sizes, uint won't be enough in the near future