tools/target_dec_fuzzer: remove calls to avcodec_register*()

They are no longer needed.

Signed-off-by: James Almer <jamrial@gmail.com>

tools/target_dec_fuzzer.c

@@ -118,17 +118,14 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
 #define DECODER_SYMBOL(CODEC) DECODER_SYMBOL0(CODEC)
         extern AVCodec DECODER_SYMBOL(FFMPEG_DECODER);
         codec_list[0] = &DECODER_SYMBOL(FFMPEG_DECODER);
-        avcodec_register(&DECODER_SYMBOL(FFMPEG_DECODER));
 
 #if FFMPEG_DECODER == tiff || FFMPEG_DECODER == tdsc
         extern AVCodec DECODER_SYMBOL(mjpeg);
         codec_list[1] = &DECODER_SYMBOL(mjpeg);
-        avcodec_register(&DECODER_SYMBOL(mjpeg));
 #endif
 
         c = &DECODER_SYMBOL(FFMPEG_DECODER);
 #else
-        avcodec_register_all();
         c = AVCodecInitialize(FFMPEG_CODEC);  // Done once.
 #endif
         av_log_set_level(AV_LOG_PANIC);