ALSA: ASoC: Fix typo in snd_soc_card update documentation

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/Documentation/sound/alsa/soc/machine.txt b/Documentation/sound/alsa/soc/machine.txt
index 4a9f51e..bab7711 100644
--- a/Documentation/sound/alsa/soc/machine.txt
+++ b/Documentation/sound/alsa/soc/machine.txt
@@ -9,7 +9,7 @@
 the following struct:-
 
 /* SoC machine */
-struct snd_soc_card {_
+struct snd_soc_card {
 	char *name;
 
 	int (*probe)(struct platform_device *pdev);