Generate mpegaudio tables only when CONFIG_HARDCODED_TABLES is set

Having mpegaudiodec.o unconditionally depend on mpegaudio_tables.h
forces the latter to be generated even when it will not be used.

Originally committed as revision 20405 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/Makefile

@@ -710,6 +710,9 @@ endif
 $(SUBDIR)%_tablegen$(HOSTEXESUF): $(SUBDIR)%_tablegen.c $(SUBDIR)tableprint.c
 	$(HOSTCC) $(HOSTCFLAGS) $(HOSTLDFLAGS) -o $@ $^ $(HOSTLIBS)
 
-$(SUBDIR)mpegaudiodec.o: $(SUBDIR)mpegaudio_tables.h
 $(SUBDIR)%_tables.h: $(SUBDIR)%_tablegen$(HOSTEXESUF)
 	./$< > $@
+
+ifdef CONFIG_HARDCODED_TABLES
+$(SUBDIR)mpegaudiodec.o: $(SUBDIR)mpegaudio_tables.h
+endif