[ALSA] Fix a typo in __dev* changes in portman2x4.c

Fix a typo in the last __dev* changes in portman2x4.c.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NJaroslav Kysela <perex@suse.cz>

sound/drivers/portman2x4.c

@@ -824,7 +824,7 @@ static int __devexit snd_portman_remove(struct platform_device *pdev)
 
 static struct platform_driver snd_portman_driver = {
 	.probe  = snd_portman_probe,
-	.remove = __dev_exit_p(snd_portman_remove),
+	.remove = __devexit_p(snd_portman_remove),
 	.driver = {
 		.name = PLATFORM_DRIVER
 	}