pinctrl: uniphier: replace printf() with dev_err()

dev_err() is more suitable for printing error messages.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/drivers/pinctrl/uniphier/pinctrl-uniphier-core.c b/drivers/pinctrl/uniphier/pinctrl-uniphier-core.c
index 7b427d0..601a42d 100644
--- a/drivers/pinctrl/uniphier/pinctrl-uniphier-core.c
+++ b/drivers/pinctrl/uniphier/pinctrl-uniphier-core.c
@@ -173,7 +173,7 @@
 		ret = uniphier_pinconf_input_enable(dev, pin, arg);
 		break;
 	default:
-		printf("unsupported configuration parameter %u\n", param);
+		dev_err(dev, "unsupported configuration parameter %u\n", param);
 		return -EINVAL;
 	}