ALSA: Add missing .owner=THIS_MODULE to platform_driver definitions

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/drivers/virmidi.c b/sound/drivers/virmidi.c
index 9d97478..d7d514d 100644
--- a/sound/drivers/virmidi.c
+++ b/sound/drivers/virmidi.c
@@ -142,7 +142,8 @@
 	.probe		= snd_virmidi_probe,
 	.remove		= __devexit_p(snd_virmidi_remove),
 	.driver		= {
-		.name	= SND_VIRMIDI_DRIVER
+		.name	= SND_VIRMIDI_DRIVER,
+		.owner	= THIS_MODULE,
 	},
 };