drivers/rtc/rtc-sa1100.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-sa1100.c b/drivers/rtc/rtc-sa1100.c
index 0f7adeb..b6e1ca0 100644
--- a/drivers/rtc/rtc-sa1100.c
+++ b/drivers/rtc/rtc-sa1100.c
@@ -338,7 +338,7 @@
 			sa1100_rtc_resume);
 
 #ifdef CONFIG_OF
-static struct of_device_id sa1100_rtc_dt_ids[] = {
+static const struct of_device_id sa1100_rtc_dt_ids[] = {
 	{ .compatible = "mrvl,sa1100-rtc", },
 	{ .compatible = "mrvl,mmp-rtc", },
 	{}