powernow_k8

[PATCH] x86: use num_online_nodes to get physical cpus numbers for powernow_k8

For opteron based system, don't assume all physical cpus have the same booted cpus even same cores. esp for downcore case.

Signed-off-by: Yinghai Lu <yinghai.sun.com>
Signed-off-by: Dave Jones <davej@redhat.com>