hwmon: (amd_energy) Missing platform_driver_unregister() on error in amd_energy_init()

Add the missing platform_driver_unregister() before return
from amd_energy_init() in the error handling case.

Fixes: 8abee956 ("hwmon: Add amd_energy driver to report energy counters")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Naveen krishna Chatradhi <nchatrad@amd.com>
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20200527022417.105620-1-weiyongjun1@huawei.comSigned-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/amd_energy.c

@@ -379,8 +379,10 @@ static int __init amd_energy_init(void)
 		return ret;
 
 	amd_energy_platdev = platform_device_alloc(DRVNAME, 0);
-	if (!amd_energy_platdev)
+	if (!amd_energy_platdev) {
+		platform_driver_unregister(&amd_energy_driver);
 		return -ENOMEM;
+	}
 
 	ret = platform_device_add(amd_energy_platdev);
 	if (ret) {