drm/panel: khadas: Fix error code in khadas_ts050_panel_add()

There is a copy and paste bug so it didn't return the correct error
code.

Fixes: b2152121 ("drm: panel: add Khadas TS050 panel driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/X9NEfmgGilaXJs2R@mwanda

drivers/gpu/drm/panel/panel-khadas-ts050.c

@@ -786,7 +786,7 @@ static int khadas_ts050_panel_add(struct khadas_ts050_panel *khadas_ts050)
 	khadas_ts050->enable_gpio = devm_gpiod_get(dev, "enable",
 						   GPIOD_OUT_HIGH);
 	if (IS_ERR(khadas_ts050->enable_gpio))
-		return dev_err_probe(dev, PTR_ERR(khadas_ts050->reset_gpio),
+		return dev_err_probe(dev, PTR_ERR(khadas_ts050->enable_gpio),
 				     "failed to get enable gpio");
 
 	drm_panel_init(&khadas_ts050->base, &khadas_ts050->link->dev,