Add void keyword to declaration of ao_default_id() in public header.

Also make same change in implementation (src/audio_out.c). Closes ticket:1086


git-svn-id: http://svn.xiph.org/trunk/ao@12204 0101bb08-14d6-0310-b084-bc0e0c8e3800

include/ao/ao.h

@@ -134,7 +134,7 @@ int ao_close(ao_device *device);
 
 /* driver information */
 int ao_driver_id(const char *short_name);
-int ao_default_driver_id();
+int ao_default_driver_id(void);
 ao_info *ao_driver_info(int driver_id);
 ao_info **ao_driver_info_list(int *driver_count);
 char *ao_file_extension(int driver_id);

src/audio_out.c

@@ -732,7 +732,7 @@ int ao_driver_id(const char *short_name)
 }
 
 
-int ao_default_driver_id ()
+int ao_default_driver_id (void)
 {
 	/* Find the default driver in the list of loaded drivers */