filters/f_lavfi: handle removed AV_OPT_TYPE_CHANNEL_LAYOUT

See: https://github.com/FFmpeg/FFmpeg/commit/65ddc74988245a01421a63c5cffa4d900c47117c

filters/f_lavfi.c

@@ -1034,7 +1034,11 @@ static const char *get_avopt_type_name(enum AVOptionType type)
     case AV_OPT_TYPE_VIDEO_RATE:        return "fps";
     case AV_OPT_TYPE_DURATION:          return "duration";
     case AV_OPT_TYPE_COLOR:             return "color";
+#if LIBAVUTIL_VERSION_MAJOR < 59
     case AV_OPT_TYPE_CHANNEL_LAYOUT:    return "channellayout";
+#else
+    case AV_OPT_TYPE_CHLAYOUT:          return "channellayout";
+#endif
     case AV_OPT_TYPE_BOOL:              return "bool";
     case AV_OPT_TYPE_CONST: // fallthrough
     default: