ACPI: Allow selection of the ACPI processor driver for ARM64

Now that the ACPI processor driver has been decoupled from
the C states and P states functionality, make it selectable on
ARM64 so that it can be used by others e.g. CPPC.

The C states and P states code is selected only on X86 or
IA64 until the relevant support is added on ARM64.

Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/Kconfig

@@ -213,9 +213,9 @@ config ACPI_CPPC_LIB
 
 config ACPI_PROCESSOR
 	tristate "Processor"
-	depends on X86 || IA64
-	select ACPI_PROCESSOR_IDLE
-	select ACPI_CPU_FREQ_PSS
+	depends on X86 || IA64 || ARM64
+	select ACPI_PROCESSOR_IDLE if X86 || IA64
+	select ACPI_CPU_FREQ_PSS if X86 || IA64
 	default y
 	help
 	  This driver adds support for the ACPI Processor package. It is required