ACPI / PNP: constify device IDs

Instead of re-creating the array on the stack each time
is_cmos_rtc_device() gets called, make the array 'static const'.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/acpi_pnp.c b/drivers/acpi/acpi_pnp.c
index 48fc3ad..67d97c0 100644
--- a/drivers/acpi/acpi_pnp.c
+++ b/drivers/acpi/acpi_pnp.c
@@ -367,7 +367,7 @@
  */
 static int is_cmos_rtc_device(struct acpi_device *adev)
 {
-	struct acpi_device_id ids[] = {
+	static const struct acpi_device_id ids[] = {
 		{ "PNP0B00" },
 		{ "PNP0B01" },
 		{ "PNP0B02" },