Drop 'vp_bits_from_cpuid' as it is not really needed.

No functional changes.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240316120706.4352-1-bp@alien8.de