ASoC: pxa: Fix module autoload for platform drivers

These platform drivers are lacking MODULE_ALIAS so module autoloading
doesn't work. Tested on corgi and poodle with kernel 4.4.

Signed-off-by: Andrea Adami <andrea.adami@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/pxa/mioa701_wm9713.c b/sound/soc/pxa/mioa701_wm9713.c
index 5c8f9db..d1661fa 100644
--- a/sound/soc/pxa/mioa701_wm9713.c
+++ b/sound/soc/pxa/mioa701_wm9713.c
@@ -207,3 +207,4 @@
 MODULE_AUTHOR("Robert Jarzmik (rjarzmik@free.fr)");
 MODULE_DESCRIPTION("ALSA SoC WM9713 MIO A701");
 MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:mioa701-wm9713");