PM / devfreq: exynos-ppmu: Handle return value of clk_prepare_enable

clk_prepare_enable() can fail here and we must check its return value.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>

drivers/devfreq/event/exynos-ppmu.c

@@ -648,7 +648,11 @@ static int exynos_ppmu_probe(struct platform_device *pdev)
 			dev_name(&pdev->dev), desc[i].name);
 	}
 
-	clk_prepare_enable(info->ppmu.clk);
+	ret = clk_prepare_enable(info->ppmu.clk);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to prepare ppmu clock\n");
+		return ret;
+	}
 
 	return 0;
 }