avformat/matroskadec: Include webm_dash_manifest demuxer only if enabled

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavformat/matroskadec.c

@@ -3885,6 +3885,7 @@ static int matroska_read_close(AVFormatContext *s)
     return 0;
 }
 
+#if CONFIG_WEBM_DASH_MANIFEST_DEMUXER
 typedef struct {
     int64_t start_time_ns;
     int64_t end_time_ns;
@@ -4292,6 +4293,18 @@ static const AVClass webm_dash_class = {
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
+const AVInputFormat ff_webm_dash_manifest_demuxer = {
+    .name           = "webm_dash_manifest",
+    .long_name      = NULL_IF_CONFIG_SMALL("WebM DASH Manifest"),
+    .priv_class     = &webm_dash_class,
+    .priv_data_size = sizeof(MatroskaDemuxContext),
+    .flags_internal = FF_FMT_INIT_CLEANUP,
+    .read_header    = webm_dash_manifest_read_header,
+    .read_packet    = webm_dash_manifest_read_packet,
+    .read_close     = matroska_read_close,
+};
+#endif
+
 const AVInputFormat ff_matroska_demuxer = {
     .name           = "matroska,webm",
     .long_name      = NULL_IF_CONFIG_SMALL("Matroska / WebM"),
@@ -4305,14 +4318,3 @@ const AVInputFormat ff_matroska_demuxer = {
     .read_seek      = matroska_read_seek,
     .mime_type      = "audio/webm,audio/x-matroska,video/webm,video/x-matroska"
 };
-
-const AVInputFormat ff_webm_dash_manifest_demuxer = {
-    .name           = "webm_dash_manifest",
-    .long_name      = NULL_IF_CONFIG_SMALL("WebM DASH Manifest"),
-    .priv_data_size = sizeof(MatroskaDemuxContext),
-    .flags_internal = FF_FMT_INIT_CLEANUP,
-    .read_header    = webm_dash_manifest_read_header,
-    .read_packet    = webm_dash_manifest_read_packet,
-    .read_close     = matroska_read_close,
-    .priv_class     = &webm_dash_class,
-};