x86/amd: Use heterogeneous core topology for identifying boost numerator

AMD heterogeneous designs include two types of cores:

 * Performance
 * Efficiency

Each core type has different highest performance values configured by the
platform.  Drivers such as amd_pstate need to identify the type of core to
correctly set an appropriate boost numerator to calculate the maximum
frequency.

X86_FEATURE_AMD_HETEROGENEOUS_CORES is used to identify whether the SoC
supports heterogeneous core type by reading CPUID leaf Fn_0x80000026.

On performance cores the scaling factor of 196 is used.  On efficiency cores
the scaling factor is the value reported as the highest perf.  Efficiency
cores have the same preferred core rankings.

Suggested-by: Perry Yuan <perry.yuan@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20241025171459.1093-6-mario.limonciello@amd.com

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