USB: cdc-acm: add device id for GW Instek AFG-2225

Add device-id entry for GW Instek AFG-2225, which has a byte swapped
bInterfaceSubClass (0x20).
Reported-by: NKarl Palsson <karlp@tweak.net.au>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NJohan Hovold <johan@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/class/cdc-acm.c

@@ -1681,6 +1681,7 @@ static const struct usb_device_id acm_ids[] = {
 	{ USB_DEVICE(0x0572, 0x1328), /* Shiro / Aztech USB MODEM UM-3100 */
 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
 	},
+	{ USB_DEVICE(0x2184, 0x001c) },	/* GW Instek AFG-2225 */
 	{ USB_DEVICE(0x22b8, 0x6425), /* Motorola MOTOMAGX phones */
 	},
 	/* Motorola H24 HSPA module: */