cpufreq/amd-pstate: Fix prefcore rankings

cpufreq/amd-pstate: Fix prefcore rankings

commit 50a062a76200 ("cpufreq/amd-pstate: Store the boost numerator as
highest perf again") updated the value stored for highest perf to no longer
store the highest perf value but instead the boost numerator.

This is a fixed value for systems with preferred cores and not appropriate
for use ITMT rankings. Update the value used for ITMT rankings to be the
preferred core ranking.

Reported-and-tested-by: Sebastian <sobrus@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219640
Fixes: 50a062a76200 ("cpufreq/amd-pstate: Store the boost numerator as highest perf again")
Reviewed-by: Dhananjay Ugwekar <dhananjay.ugwekar@amd.com>
Link: https://lore.kernel.org/r/20250102141204.3413202-1-superm1@kernel.org
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>