drm/bridge/tc358775: Fix for PTR_ERR

passing zero to 'PTR_ERR'
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NVinay Simha BN <simhavcs@gmail.com>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1597557042-5154-1-git-send-email-simhavcs@gmail.com

drivers/gpu/drm/bridge/tc358775.c

@@ -684,7 +684,7 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
 
 	tc->vdd = devm_regulator_get(dev, "vdd-supply");
 	if (IS_ERR(tc->vdd)) {
-		ret = PTR_ERR(tc->vddio);
+		ret = PTR_ERR(tc->vdd);
 		dev_err(dev, "vdd-supply not found\n");
 		return ret;
 	}