HID: Ignore battery for Elan touchscreen on ASUS UX550

Battery status is being reported for the Elan touchscreen on ASUS
UX550 laptops despite not having a batter. It always shows either 0 or
1%.
Signed-off-by: Seth Miller <miller.seth@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/hid-ids.h

@@ -389,6 +389,7 @@
 #define USB_DEVICE_ID_TOSHIBA_CLICK_L9W	0x0401
 #define USB_DEVICE_ID_HP_X2		0x074d
 #define USB_DEVICE_ID_HP_X2_10_COVER	0x0755
+#define USB_DEVICE_ID_ASUS_UX550_TOUCHSCREEN	0x2706
 
 #define USB_VENDOR_ID_ELECOM		0x056e
 #define USB_DEVICE_ID_ELECOM_BM084	0x0061

drivers/hid/hid-input.c

@@ -322,6 +322,8 @@ static const struct hid_device_id hid_battery_quirks[] = {
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_LOGITECH,
 		USB_DEVICE_ID_LOGITECH_DINOVO_EDGE_KBD),
 	  HID_BATTERY_QUIRK_IGNORE },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_ELAN, USB_DEVICE_ID_ASUS_UX550_TOUCHSCREEN),
+	  HID_BATTERY_QUIRK_IGNORE },
 	{}
 };