avcodec/sinewin: Fix wrong number of elements of array declaration

There are actually only 14 elements in each ff_sine_windows array.
Signed-off-by: NAndreas Rheinhardt <andreas.rheinhardt@gmail.com>

libavcodec/sinewin.h

@@ -60,6 +60,6 @@ extern SINETABLE(2048);
 extern SINETABLE(4096);
 extern SINETABLE(8192);
 
-extern SINETABLE_CONST INTFLOAT * const AAC_RENAME(ff_sine_windows)[16];
+extern SINETABLE_CONST INTFLOAT * const AAC_RENAME(ff_sine_windows)[];
 
 #endif /* AVCODEC_SINEWIN_H */