ASoC: mid-x86: Add .owner to struct snd_soc_card

Add missing .owner of struct snd_soc_card. This prevents the module from being
removed from underneath its users.
Reported-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/mid-x86/mfld_machine.c

@@ -323,6 +323,7 @@ static struct snd_soc_dai_link mfld_msic_dailink[] = {
 /* SoC card */
 static struct snd_soc_card snd_soc_card_mfld = {
 	.name = "medfield_audio",
+	.owner = THIS_MODULE,
 	.dai_link = mfld_msic_dailink,
 	.num_links = ARRAY_SIZE(mfld_msic_dailink),
 };