ASoC: omap: rx51: Add module alias

Add module alias to support driver autoloading.

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/sound/soc/omap/rx51.c b/sound/soc/omap/rx51.c
index 1a3f05c..55713d0 100644
--- a/sound/soc/omap/rx51.c
+++ b/sound/soc/omap/rx51.c
@@ -421,3 +421,4 @@
 MODULE_AUTHOR("Nokia Corporation");
 MODULE_DESCRIPTION("ALSA SoC Nokia RX-51");
 MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:rx51-audio");