Input: make i2c device ids constant

The id_table field of the struct i2c_driver is defined as constant
in <linux/i2c.h> so it makes sense to mark the initialization data also
constant.

Signed-off-by: Márton Németh <nm127@freemail.hu>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/misc/apanel.c b/drivers/input/misc/apanel.c
index 71b8243..a8d2b8d 100644
--- a/drivers/input/misc/apanel.c
+++ b/drivers/input/misc/apanel.c
@@ -149,7 +149,7 @@
 	apanel_remove(client);
 }
 
-static struct i2c_device_id apanel_id[] = {
+static const struct i2c_device_id apanel_id[] = {
 	{ "fujitsu_apanel", 0 },
 	{ }
 };