regulator: Convert to using %pOFn instead of device_node.name

In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/regulator/max8997-regulator.c b/drivers/regulator/max8997-regulator.c
index ad0c806..3bf5ddf 100644
--- a/drivers/regulator/max8997-regulator.c
+++ b/drivers/regulator/max8997-regulator.c
@@ -929,8 +929,8 @@ static int max8997_pmic_dt_parse_pdata(struct platform_device *pdev,
 				break;
 
 		if (i == ARRAY_SIZE(regulators)) {
-			dev_warn(&pdev->dev, "don't know how to configure regulator %s\n",
-				 reg_np->name);
+			dev_warn(&pdev->dev, "don't know how to configure regulator %pOFn\n",
+				 reg_np);
 			continue;
 		}