MINOR: cpu-topo: fall back to nominal_perf and scaling_max_freq for the capacity

MINOR: cpu-topo: fall back to nominal_perf and scaling_max_freq for the capacity

When cpu_capacity is not present, let's try to check acpi_cppc's
nominal_perf which is similar and commonly found on servers, then
scaling_max_freq (though that last one may vary a bit between CPUs
depending on die quality). That variation is not a problem since
we can absorb a ~5% variation without issue.

It was verified on an i9-14900 featuring 5.7-P, 6.0-P and 4.4-E GHz
that P-cores were not reordered and that E cores were placed last.
It was also OK on a W3-2345 with 4.3 to 4.5GHz.