Update codecs detection for Safari browsers

pkg/mp4/helpers.go

@@ -55,7 +55,6 @@ func ParseCodecs(codecs string, parseAudio bool) (medias []*core.Media) {
 	var videos []*core.Codec
 	var audios []*core.Codec
 
-loop:
 	for _, name := range strings.Split(codecs, ",") {
 		switch name {
 		case MimeH264:
@@ -67,10 +66,6 @@ loop:
 		case MimeAAC:
 			codec := &core.Codec{Name: core.CodecAAC}
 			audios = append(audios, codec)
-		case "null":
-			// this means that the browser is lying about the codecs it can play
-			// and we are not supposed to believe that it can flac or opus
-			break loop
 		case MimeFlac:
 			audios = append(audios,
 				&core.Codec{Name: core.CodecPCMA},