swfenc: use av_assert

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/swfenc.c

@@ -21,6 +21,7 @@
  */
 
 #include "libavcodec/put_bits.h"
+#include "libavutil/avassert.h"
 #include "avformat.h"
 #include "swf.h"
 
@@ -56,7 +57,7 @@ static void put_swf_end_tag(AVFormatContext *s)
         avio_wl16(pb, (tag << 6) | 0x3f);
         avio_wl32(pb, tag_len - 4);
     } else {
-        assert(tag_len < 0x3f);
+        av_assert0(tag_len < 0x3f);
         avio_wl16(pb, (tag << 6) | tag_len);
     }
     avio_seek(pb, pos, SEEK_SET);