soc: fsl: guts: use of_root instead of own reference

There is already a global of_root reference. Use that instead of getting
one on our own. We don't need to care about the reference count either
this way.
Signed-off-by: Michael Walle <michael@walle.cc>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

drivers/soc/fsl/guts.c

@@ -112,7 +112,7 @@ static const struct fsl_soc_die_attr *fsl_soc_die_match(
 
 static int fsl_guts_probe(struct platform_device *pdev)
 {
-	struct device_node *root, *np = pdev->dev.of_node;
+	struct device_node *np = pdev->dev.of_node;
 	struct soc_device_attribute *soc_dev_attr;
 	static struct soc_device *soc_dev;
 	struct device *dev = &pdev->dev;
@@ -138,17 +138,13 @@ static int fsl_guts_probe(struct platform_device *pdev)
 	if (!soc_dev_attr)
 		return -ENOMEM;
 
-	root = of_find_node_by_path("/");
-	if (of_property_read_string(root, "model", &machine))
-		of_property_read_string_index(root, "compatible", 0, &machine);
+	if (of_property_read_string(of_root, "model", &machine))
+		of_property_read_string_index(of_root, "compatible", 0, &machine);
 	if (machine) {
 		soc_dev_attr->machine = devm_kstrdup(dev, machine, GFP_KERNEL);
-		if (!soc_dev_attr->machine) {
-			of_node_put(root);
+		if (!soc_dev_attr->machine)
 			return -ENOMEM;
-		}
 	}
-	of_node_put(root);
 
 	soc_die = fsl_soc_die_match(svr, fsl_soc_die);
 	if (soc_die) {