regulator: wm831x-isink: Remove redundant error message

kzalloc prints its own OOM message upon failure.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

drivers/regulator/wm831x-isink.c

@@ -165,10 +165,8 @@ static int wm831x_isink_probe(struct platform_device *pdev)
 
 	isink = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_isink),
 			     GFP_KERNEL);
-	if (isink == NULL) {
-		dev_err(&pdev->dev, "Unable to allocate private data\n");
+	if (!isink)
 		return -ENOMEM;
-	}
 
 	isink->wm831x = wm831x;