HID: hid-multitouch: add support for the IDEACOM 6650 chip

The IDEACOM 6650 multitouch chip, present in various all-in-one computers,
uses the serial version of the HID multitouch protocol. No existing class
supports this.

In principle, the new MT_CLS_SERIAL should work for other
serial panels as well, perhaps including some eGalax panels.

Signed-off-by: Stephane Chatty <chatty@enac.fr>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 11b3b39..956f849 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1388,6 +1388,7 @@
 	{ HID_USB_DEVICE(USB_VENDOR_ID_GYRATION, USB_DEVICE_ID_GYRATION_REMOTE_2) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_GYRATION, USB_DEVICE_ID_GYRATION_REMOTE_3) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_HANVON, USB_DEVICE_ID_HANVON_MULTITOUCH) },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_IDEACOM, USB_DEVICE_ID_IDEACOM_IDC6650) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_HOLTEK, USB_DEVICE_ID_HOLTEK_ON_LINE_GRIP) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ILITEK, USB_DEVICE_ID_ILITEK_MULTITOUCH) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_IRTOUCHSYSTEMS, USB_DEVICE_ID_IRTOUCH_INFRARED_USB) },