sound: Add module.h to the previously silent sound users

Lots of sound drivers were getting module.h via the implicit presence
of it in <linux/device.h> but we are going to clean that up.  So
fix up those users now.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/sound/synth/emux/emux_seq.c b/sound/synth/emux/emux_seq.c
index ca5f7ef..7778b8e 100644
--- a/sound/synth/emux/emux_seq.c
+++ b/sound/synth/emux/emux_seq.c
@@ -21,7 +21,7 @@
 
 #include "emux_voice.h"
 #include <linux/slab.h>
-
+#include <linux/module.h>
 
 /* Prototypes for static functions */
 static void free_port(void *private);