tools/power turbostat: Process HT siblings in CPU order
On large systems with HT sibling cpu#'s more than 32 apart,
HT siblings were processed and displayed in reverse order.
This was due to how set_thread_siblings() parsed the
sibling-bit-mask.
Update set_thread_siblings to instead parse the sibling-list,
like other cpu lists, and to thus order HT siblings
by ascending CPU number, no matter the size of the system.