cpufreq: imx6q: Switch to use dev_err_probe() helper

In the probe path, dev_err() can be replaced with dev_err_probe()
which will check if error code is -EPROBE_DEFER and prints the
error name. It also sets the defer probe reason which can be
checked later through debugfs. It's more simple in error path.
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

drivers/cpufreq/imx6q-cpufreq.c

@@ -396,9 +396,7 @@ static int imx6q_cpufreq_probe(struct platform_device *pdev)
 		ret = imx6q_opp_check_speed_grading(cpu_dev);
 	}
 	if (ret) {
-		if (ret != -EPROBE_DEFER)
-			dev_err(cpu_dev, "failed to read ocotp: %d\n",
-				ret);
+		dev_err_probe(cpu_dev, ret, "failed to read ocotp\n");
 		goto out_free_opp;
 	}