[ALSA] unregister platform device again if probe was unsuccessful

Unregister the platform device again if the probe was unsuccessful.

This restores the behaviour of not loading the driver on probe() failure.

Signed-off-by: Rene Herman <rene.herman@keyaccess.nl>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/isa/gus/gusclassic.c

@@ -255,6 +255,10 @@ static int __init alsa_card_gusclassic_init(void)
 							 i, NULL, 0);
 		if (IS_ERR(device))
 			continue;
+		if (!platform_get_drvdata(device)) {
+			platform_device_unregister(device);
+			continue;
+		}
 		devices[i] = device;
 		cards++;
 	}