Input: mtouch - constify serio_device_id

serio_device_id are not supposed to change at runtime. All functions
working with serio_device_id provided by <linux/serio.h> work with
const serio_device_id. So mark the non-const structs as const.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/mtouch.c

@@ -178,7 +178,7 @@ static int mtouch_connect(struct serio *serio, struct serio_driver *drv)
  * The serio driver structure.
  */
 
-static struct serio_device_id mtouch_serio_ids[] = {
+static const struct serio_device_id mtouch_serio_ids[] = {
 	{
 		.type	= SERIO_RS232,
 		.proto	= SERIO_MICROTOUCH,