thermal/drivers: imx: Fix missing of_node_put() at probe time

After finishing using cpu node got from of_get_cpu_node(), of_node_put()
needs to be called.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/1585232945-23368-1-git-send-email-Anson.Huang@nxp.com

drivers/thermal/imx_thermal.c

@@ -649,7 +649,7 @@ MODULE_DEVICE_TABLE(of, of_imx_thermal_match);
 static int imx_thermal_register_legacy_cooling(struct imx_thermal_data *data)
 {
 	struct device_node *np;
-	int ret;
+	int ret = 0;
 
 	data->policy = cpufreq_cpu_get(0);
 	if (!data->policy) {
@@ -664,11 +664,12 @@ static int imx_thermal_register_legacy_cooling(struct imx_thermal_data *data)
 		if (IS_ERR(data->cdev)) {
 			ret = PTR_ERR(data->cdev);
 			cpufreq_cpu_put(data->policy);
-			return ret;
 		}
 	}
 
-	return 0;
+	of_node_put(np);
+
+	return ret;
 }
 
 static void imx_thermal_unregister_legacy_cooling(struct imx_thermal_data *data)