rtc: make of_device_ids const

of_device_ids (i.e. compatible strings and the respective data) are not
supposed to change at runtime.  All functions working with of_device_ids
provided by <linux/of.h> work with const of_device_ids.  This allows to
mark all struct of_device_id below drivers/rtc const, too.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-isl12022.c

@@ -274,7 +274,7 @@ static int isl12022_probe(struct i2c_client *client,
 }
 
 #ifdef CONFIG_OF
-static struct of_device_id isl12022_dt_match[] = {
+static const struct of_device_id isl12022_dt_match[] = {
 	{ .compatible = "isl,isl12022" },
 	{ },
 };

drivers/rtc/rtc-mpc5121.c

@@ -401,7 +401,7 @@ static int mpc5121_rtc_remove(struct platform_device *op)
 }
 
 #ifdef CONFIG_OF
-static struct of_device_id mpc5121_rtc_match[] = {
+static const struct of_device_id mpc5121_rtc_match[] = {
 	{ .compatible = "fsl,mpc5121-rtc", },
 	{ .compatible = "fsl,mpc5200-rtc", },
 	{},