drivers/rtc/rtc-pxa.c: make of_device_id array const

Make of_device_id array const, because all OF functions handle
it as const.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-pxa.c b/drivers/rtc/rtc-pxa.c
index cccbf9d..4561f37 100644
--- a/drivers/rtc/rtc-pxa.c
+++ b/drivers/rtc/rtc-pxa.c
@@ -389,7 +389,7 @@
 }
 
 #ifdef CONFIG_OF
-static struct of_device_id pxa_rtc_dt_ids[] = {
+static const struct of_device_id pxa_rtc_dt_ids[] = {
 	{ .compatible = "marvell,pxa-rtc" },
 	{}
 };