cpufreq/amd-pstate: store all values in cpudata struct in khz

Storing values in the cpudata structure in different units leads
to confusion and hardcoded conversions elsewhere.  After ratios are
calculated store everything in khz for any future use. Adjust all
relevant consumers for this change as well.

Suggested-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@amd.com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Link: https://lore.kernel.org/r/20241209185248.16301-9-mario.limonciello@amd.com


Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>