apetag: fix comment

Signed-off-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Justin Ruggles <justin.ruggles@gmail.com>

libavformat/apetag.h

@@ -30,4 +30,4 @@
  */
 void ff_ape_parse_tag(AVFormatContext *s);
 
-#endif /* AVFORMAT_ID3V2_H */
+#endif /* AVFORMAT_APETAG_H */