aac: fix build with hardcoded tables

aac_tablegen.h includes aac.h for the POW_SF2_ZERO definition, but
this also pulls in a raft of other headers, some of which are not
safe to use in code built with the host compiler.

Moving POW_SF2_ZERO to aac_tablegen_decl.h, where the declaration
of the array it relates to already resides, fixes the problems.
Signed-off-by: Mans Rullgard <mans@mansr.com>

libavcodec/aac.h

@@ -141,7 +141,6 @@ typedef struct PredictorState {
 #define SCALE_MAX_POS   255    ///< scalefactor index maximum value
 #define SCALE_MAX_DIFF   60    ///< maximum scalefactor difference allowed by standard
 #define SCALE_DIFF_ZERO  60    ///< codebook index corresponding to zero scalefactor indices difference
-#define POW_SF2_ZERO    200    ///< ff_aac_pow2sf_tab index corresponding to pow(2, 0);
 
 /**
  * Long Term Prediction

libavcodec/aac_tablegen.h

@@ -29,7 +29,6 @@
 #include "libavcodec/aac_tables.h"
 #else
 #include "libavutil/mathematics.h"
-#include "aac.h"
 float ff_aac_pow2sf_tab[428];
 
 void ff_aac_tableinit(void)

libavcodec/aac_tablegen_decl.h

@@ -23,6 +23,8 @@
 #ifndef AVCODEC_AAC_TABLEGEN_DECL_H
 #define AVCODEC_AAC_TABLEGEN_DECL_H
 
+#define POW_SF2_ZERO    200    ///< ff_aac_pow2sf_tab index corresponding to pow(2, 0);
+
 #if CONFIG_HARDCODED_TABLES
 #define ff_aac_tableinit()
 extern const float ff_aac_pow2sf_tab[428];