Driver core: make struct platform_driver.id_table const

This fixes a warning on several pxa based machines:

	arch/arm/mach-pxa/ssp.c:475: warning: initialization discards qualifiers from pointer target type
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: NVikram Dhillon <dhillonv10@gmail.com>
Acked-by: NEric Miao <eric.y.miao@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/base/platform.c

@@ -636,7 +636,7 @@ static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
 }
 
 static const struct platform_device_id *platform_match_id(
-			struct platform_device_id *id,
+			const struct platform_device_id *id,
 			struct platform_device *pdev)
 {
 	while (id->name[0]) {

include/linux/platform_device.h

@@ -62,7 +62,7 @@ struct platform_driver {
 	int (*suspend)(struct platform_device *, pm_message_t state);
 	int (*resume)(struct platform_device *);
 	struct device_driver driver;
-	struct platform_device_id *id_table;
+	const struct platform_device_id *id_table;
 };
 
 extern int platform_driver_register(struct platform_driver *);