mux: drop the warning about global headers

The AVStream codec context is often not (and should not be) the actual
encoding context, so this warning will be spurious in many cases.

libavformat/mux.c

@@ -199,12 +199,6 @@ FF_ENABLE_DEPRECATION_WARNINGS
                 codec->codec_tag = av_codec_get_tag(of->codec_tag, codec->codec_id);
         }
 
-        if (of->flags & AVFMT_GLOBALHEADER &&
-            !(codec->flags & AV_CODEC_FLAG_GLOBAL_HEADER))
-            av_log(s, AV_LOG_WARNING,
-                   "Codec for stream %d does not use global headers "
-                   "but container format requires global headers\n", i);
-
         if (codec->codec_type != AVMEDIA_TYPE_ATTACHMENT)
             s->internal->nb_interleaved_streams++;
     }