avcodec/aactab: Fix conflicting types for ff_aac_codebook*

The header missed that these are arrays of const pointers (to const
data).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

libavcodec/aactab.h

@@ -167,9 +167,9 @@ extern const uint16_t * const ff_aac_spectral_codes[11];
 extern const uint8_t  * const ff_aac_spectral_bits [11];
 extern const uint16_t  ff_aac_spectral_sizes[11];
 
-extern const float *ff_aac_codebook_vectors[];
-extern const float *ff_aac_codebook_vector_vals[];
-extern const uint16_t *ff_aac_codebook_vector_idx[];
+extern const float *const ff_aac_codebook_vectors[];
+extern const float *const ff_aac_codebook_vector_vals[];
+extern const uint16_t *const ff_aac_codebook_vector_idx[];
 
 extern const uint16_t * const ff_swb_offset_1024[13];
 extern const uint16_t * const ff_swb_offset_960 [13];