aacenc: move the generation of ff_aac_pow34sf_tab[]

This commit moves the generation of ff_aac_pow34sf_tab[] out of the
encoder and into the table generator. The original commit log for
this table in 2011 actually mentions that it should be moved outside
but this never happened.

This is the first commit which cleans up the encoder a little.

Reviewed-by: Claudio Freire <klaussfreire@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavcodec/aaccoder.c

@@ -39,6 +39,7 @@
 #include "aac.h"
 #include "aacenc.h"
 #include "aactab.h"
+#include "aac_tablegen_decl.h"
 
 /** Frequency in Hz for lower limit of noise substitution **/
 #define NOISE_LOW_LIMIT 4500