Drop typedef redeclarations

C99 doesn't permit redeclaring typedefs in the same scope.

src/audio_call.c

@@ -6,8 +6,8 @@
 #include "config.h"
 #endif
 
-#include "audio_call.h"
 #include "toxic_windows.h"
+#include "audio_call.h"
 #include "chat_commands.h"
 #include "global_commands.h"
 #include "toxic_windows.h"

src/audio_call.h

@@ -7,8 +7,6 @@
 
 #include <tox/toxav.h>
 
-typedef struct ToxWindow ToxWindow;
-
 typedef enum _AudioError
 {
     NoError = 0,
@@ -27,4 +25,4 @@ int errors();
 
 int start_transmission(ToxWindow *self);
 
-#endif /* _audio_h */
+#endif /* _audio_h */