ffplay: remove now unnecessary request_channels, we set it now with options

ffplay.c

@@ -2160,15 +2160,6 @@ static int stream_component_open(VideoState *is, int stream_index)
 
     opts = filter_codec_opts(codec_opts, avctx->codec_id, ic, ic->streams[stream_index]);
 
-    /* prepare audio output */
-    if (avctx->codec_type == AVMEDIA_TYPE_AUDIO) {
-        if (avctx->channels > 0) {
-            avctx->request_channels = FFMIN(2, avctx->channels);
-        } else {
-            avctx->request_channels = 2;
-        }
-    }
-
     codec = avcodec_find_decoder(avctx->codec_id);
     switch(avctx->codec_type){
         case AVMEDIA_TYPE_AUDIO   : if(audio_codec_name   ) codec= avcodec_find_decoder_by_name(   audio_codec_name); break;