drm: display: Set fwnode for aux bus devices

fwnode needs to be set for a device for fw_devlink to be able to
track/enforce its dependencies correctly. Without this, you'll see error
messages like this when the supplier has probed and tries to make sure
all its fwnode consumers are linked to it using device links:

mediatek-drm-dp 1c500000.edp-tx: Failed to create device link (0x180) with backlight-lcd0

Reported-by: Nícolas F. R. A. Prado <[email protected]>
Closes: https://lore.kernel.org/all/7b995947-4540-4b17-872e-e107adca4598@notapiano/
Tested-by: Nícolas F. R. A. Prado <[email protected]>
Signed-off-by: Saravana Kannan <[email protected]>
Reviewed-by: Dmitry Baryshkov <[email protected]>
Reviewed-by: Thierry Reding <[email protected]>
Tested-by: AngeloGioacchino Del Regno <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: Saravana Kannan

drivers/gpu/drm/display/drm_dp_aux_bus.c

@@ -292,7 +292,7 @@ int of_dp_aux_populate_bus(struct drm_dp_aux *aux,
 	aux_ep->dev.parent = aux->dev;
 	aux_ep->dev.bus = &dp_aux_bus_type;
 	aux_ep->dev.type = &dp_aux_device_type_type;
-	aux_ep->dev.of_node = of_node_get(np);
+	device_set_node(&aux_ep->dev, of_fwnode_handle(of_node_get(np)));
 	dev_set_name(&aux_ep->dev, "aux-%s", dev_name(aux->dev));
 
 	ret = device_register(&aux_ep->dev);