Revert "Add required header #include to fix 'make checkheaders'."

config.h must not be included in that file.  The table generator runs
on the host system, but config.h describes the target.

Originally committed as revision 20620 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/mpegaudio_tablegen.h

@@ -27,7 +27,6 @@
 // do not use libavutil/mathematics.h since this is compiled both
 // for the host and the target and config.h is only valid for the target
 #include <math.h>
-#include "config.h"
 
 #define TABLE_4_3_SIZE (8191 + 16)*4
 #if CONFIG_HARDCODED_TABLES