ACPI: processor_perflib: extend X86 dependency

ACPI: processor_perflib: extend X86 dependency

The majority of the processor_perflib code is only used by cpufreq
drivers on the x86 architecture and makes no sense without the
x86 SMI interactions that rely on I/O port access.

Replace the existing #ifdef checks with one that covers all of the
code that is only used by x86 drivers, saving a little bit
of kernel code size on other architectures.

There is likely more code under CONFIG_ACPI_PROCESSOR that falls
into this category, but changing those would require a larger
rework.

Suggested-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20241030123701.1538919-1-arnd@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>