r8153_ecm: Add Lenovo Powered USB-C Hub as a fallback of r8152

This commit enables the use of the r8153_ecm driver, introduced with
commit c1aedf01 ("net/usb/r8153_ecm: support ECM mode for
RTL8153") for the Lenovo Powered USB-C Hub (17ef:721e) based on the
Realtek RTL8153B chip.

This results in the following driver preference:

- if r8152 is available, use the r8152 driver
- if r8152 is not available, use the r8153_ecm driver

This is done to prevent the NIC from constantly sending pause frames
when the host system enters standby (fixed by using the r8152 driver
in "r8152: Add Lenovo Powered USB-C Travel Hub"), while still allowing
the device to work with the r8153_ecm driver as a fallback.
Signed-off-by: Leon Schuermann <leon@is.currently.online>
Tested-by: Leon Schuermann <leon@is.currently.online>
Link: https://lore.kernel.org/r/20210111190312.12589-3-leon@is.currently.onlineSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/usb/r8153_ecm.c

@@ -122,12 +122,20 @@ static const struct driver_info r8153_info = {
 };
 
 static const struct usb_device_id products[] = {
+/* Realtek RTL8153 Based USB 3.0 Ethernet Adapters */
 {
 	USB_DEVICE_AND_INTERFACE_INFO(VENDOR_ID_REALTEK, 0x8153, USB_CLASS_COMM,
 				      USB_CDC_SUBCLASS_ETHERNET, USB_CDC_PROTO_NONE),
 	.driver_info = (unsigned long)&r8153_info,
 },
 
+/* Lenovo Powered USB-C Travel Hub (4X90S92381, based on Realtek RTL8153) */
+{
+	USB_DEVICE_AND_INTERFACE_INFO(VENDOR_ID_LENOVO, 0x721e, USB_CLASS_COMM,
+				      USB_CDC_SUBCLASS_ETHERNET, USB_CDC_PROTO_NONE),
+	.driver_info = (unsigned long)&r8153_info,
+},
+
 	{ },		/* END */
 };
 MODULE_DEVICE_TABLE(usb, products);