Input: xpad - constify usb_device_id

usb_device_id are not supposed to change at runtime. All functions
working with usb_device_id provided by <linux/usb.h> work with
const usb_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/joystick/xpad.c

@@ -408,7 +408,7 @@ static const signed short xpad_abs_triggers[] = {
 #define XPAD_XBOXONE_VENDOR(vend) \
 	{ XPAD_XBOXONE_VENDOR_PROTOCOL(vend, 208) }
 
-static struct usb_device_id xpad_table[] = {
+static const struct usb_device_id xpad_table[] = {
 	{ USB_INTERFACE_INFO('X', 'B', 0) },	/* X-Box USB-IF not approved class */
 	XPAD_XBOX360_VENDOR(0x044f),		/* Thrustmaster X-Box 360 controllers */
 	XPAD_XBOX360_VENDOR(0x045e),		/* Microsoft X-Box 360 controllers */