mfd: ab8500-gpadc: Suppress 'ignoring regulator_enable() return value' warning

drivers/mfd/ab8500-gpadc.c: In function ‘ab8500_gpadc_resume’:
drivers/mfd/ab8500-gpadc.c:911:18: warning: ignoring return value of
        ‘regulator_enable’, declared with attribute warn_unused_result
        [-Wunused-result]

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/mfd/ab8500-gpadc.c

@@ -907,14 +907,17 @@ static int ab8500_gpadc_suspend(struct device *dev)
 static int ab8500_gpadc_resume(struct device *dev)
 {
 	struct ab8500_gpadc *gpadc = dev_get_drvdata(dev);
+	int ret;
 
-	regulator_enable(gpadc->regu);
+	ret = regulator_enable(gpadc->regu);
+	if (ret)
+		dev_err(dev, "Failed to enable vtvout LDO: %d\n", ret);
 
 	pm_runtime_mark_last_busy(gpadc->dev);
 	pm_runtime_put_autosuspend(gpadc->dev);
 
 	mutex_unlock(&gpadc->ab8500_gpadc_lock);
-	return 0;
+	return ret;
 }
 
 static int ab8500_gpadc_probe(struct platform_device *pdev)