cpufreq: acpi-cpufreq: Mark sometimes used ID structs as __maybe_unused

Not used when MODULE is not defined.

Fixes the following W=1 kernel build warning(s):

 drivers/cpufreq/acpi-cpufreq.c:1004:36: warning: ‘processor_device_ids’ defined but not used [-Wunused-const-variable=]
 997 | static const struct x86_cpu_id acpi_cpufreq_ids[] = {
 | ^~~~~~~~~~~~~~~~
 drivers/cpufreq/acpi-cpufreq.c:997:32: warning: ‘acpi_cpufreq_ids’ defined but not used [-Wunused-const-variable=]
 619 | static const struct acpi_device_id processor_device_ids[] = {
 | ^~~~~~~~~~~~~~~~~~~~
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpufreq/acpi-cpufreq.c

@@ -993,14 +993,14 @@ MODULE_PARM_DESC(acpi_pstate_strict,
 late_initcall(acpi_cpufreq_init);
 module_exit(acpi_cpufreq_exit);
 
-static const struct x86_cpu_id acpi_cpufreq_ids[] = {
+static const struct x86_cpu_id __maybe_unused acpi_cpufreq_ids[] = {
 	X86_MATCH_FEATURE(X86_FEATURE_ACPI, NULL),
 	X86_MATCH_FEATURE(X86_FEATURE_HW_PSTATE, NULL),
 	{}
 };
 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
 
-static const struct acpi_device_id processor_device_ids[] = {
+static const struct acpi_device_id __maybe_unused processor_device_ids[] = {
 	{ACPI_PROCESSOR_OBJECT_HID, },
 	{ACPI_PROCESSOR_DEVICE_HID, },
 	{},