ALSA: pxa2xx-ac97: Remove redundant platform_set_drvdata()

Commit 0998d063 (device-core: Ensure drvdata = NULL when no
driver is bound) removes the need to set driver data field to
NULL.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Cc: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

sound/arm/pxa2xx-ac97.c

@@ -230,7 +230,6 @@ static int pxa2xx_ac97_remove(struct platform_device *dev)
 
 	if (card) {
 		snd_card_free(card);
-		platform_set_drvdata(dev, NULL);
 		pxa2xx_ac97_hw_remove(dev);
 	}