src/libvlc.h: remove superfluous definition of vlc_rewinddir

The definition for vlc_rewinddir has been moved to include/vlc_fs.h. It
conflicted with the definition in src/libvlc.h.

src/libvlc.h

@@ -327,11 +327,9 @@ VLC_EXPORT( void, stats_DumpInputStats, (input_stats_t *) );
 void *vlc_wopendir (const wchar_t *);
 void *vlc_wclosedir (void *);
 struct _wdirent *vlc_wreaddir (void *);
-void vlc_rewinddir (void *);
 #   define _wopendir vlc_wopendir
 #   define _wreaddir vlc_wreaddir
 #   define _wclosedir vlc_wclosedir
-#   define rewinddir vlc_rewinddir
 #endif
 
 #endif