pinctrl: berlin: fix an error code in berlin_pinctrl_probe()

We are returning success here because PTR_ERR(NULL) is zero.  We should
be returning -ENODEV.

Fixes: 3de68d331c24 ('pinctrl: berlin: add the core pinctrl driver for Marvell Berlin SoCs')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/berlin/berlin.c b/drivers/pinctrl/berlin/berlin.c
index edf5d2f..86db223 100644
--- a/drivers/pinctrl/berlin/berlin.c
+++ b/drivers/pinctrl/berlin/berlin.c
@@ -320,7 +320,7 @@
 
 	regmap = dev_get_regmap(&pdev->dev, NULL);
 	if (!regmap)
-		return PTR_ERR(regmap);
+		return -ENODEV;
 
 	pctrl = devm_kzalloc(dev, sizeof(*pctrl), GFP_KERNEL);
 	if (!pctrl)