cpufreq: loongson3: Check for error code from devm_mutex_init() call

Even if it's not critical, the avoidance of checking the error code
from devm_mutex_init() call today diminishes the point of using devm
variant of it. Tomorrow it may even leak something. Add the missed
check.

Fixes: ccf51454145b ("cpufreq: Add Loongson-3 CPUFreq driver support")
Signed-off-by: Andy Shevchenko <[e-mail]>
Signed-off-by: Viresh Kumar <[e-mail]>

drivers/cpufreq/loongson3_cpufreq.c

···
 {
 	int i, ret;
 
-	for (i = 0; i < MAX_PACKAGES; i++)
-		devm_mutex_init(&pdev->dev, &cpufreq_mutex[i]);
+	for (i = 0; i < MAX_PACKAGES; i++) {
+		ret = devm_mutex_init(&pdev->dev, &cpufreq_mutex[i]);
+		if (ret)
+			return ret;
+	}
 
 	ret = do_service_request(0, 0, CMD_GET_VERSION, 0, 0);
 	if (ret <= 0)