ffplay: do not call avcodec_register_all() explicitly

avcodec_register_all() is implicitly called by av_register_all().

ffplay.c

@@ -3548,7 +3548,6 @@ int main(int argc, char **argv)
     parse_loglevel(argc, argv, options);
 
     /* register all codecs, demux and protocols */
-    avcodec_register_all();
 #if CONFIG_AVDEVICE
     avdevice_register_all();
 #endif