mastroka audio muxer: Set long_name to Matroska Audio so that it differs from...

mastroka audio muxer: Set long_name to Matroska Audio so that it differs from the long_name of matroska video.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/matroskaenc.c

@@ -1695,7 +1695,7 @@ static const AVClass mka_class = {
 };
 AVOutputFormat ff_matroska_audio_muxer = {
     .name              = "matroska",
-    .long_name         = NULL_IF_CONFIG_SMALL("Matroska"),
+    .long_name         = NULL_IF_CONFIG_SMALL("Matroska Audio"),
     .mime_type         = "audio/x-matroska",
     .extensions        = "mka",
     .priv_data_size    = sizeof(MatroskaMuxContext),