ASoC: doc: Add documentation to MAINTAINERS patterns

Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index bf61e04..8ca83d9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7662,6 +7662,7 @@
 L:	alsa-devel@alsa-project.org (moderated for non-subscribers)
 W:	http://alsa-project.org/main/index.php/ASoC
 S:	Supported
+F:	Documentation/sound/alsa/soc/
 F:	sound/soc/
 F:	include/sound/soc*