ACPI / processor: constify DMI system id table

There is no need to have processor_power_dmi_table[] writeable, constify
it.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 39e0c8e..d540f42 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -94,7 +94,7 @@
 	return 0;
 }
 
-static struct dmi_system_id processor_power_dmi_table[] = {
+static const struct dmi_system_id processor_power_dmi_table[] = {
 	{ set_max_cstate, "Clevo 5600D", {
 	  DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"),
 	  DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")},