Fix a compile warning when compiling with DEBUG=1. The warning was:

format ‘%d’ expects type ‘int’, but argument 3 has type ‘uint64_t’

Patch by Zhentan Feng <spyfeng gmail com>.

Originally committed as revision 24359 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/mmst.c

@@ -444,7 +444,7 @@ static int asf_header_parser(MMSContext *mms)
     while(end - p >= sizeof(ff_asf_guid) + 8) {
         uint64_t chunksize = AV_RL64(p + sizeof(ff_asf_guid));
         if (!chunksize || chunksize > end - p) {
-            dprintf(NULL, "chunksize is exceptional value:%d!\n", chunksize);
+            dprintf(NULL, "chunksize is exceptional value:%"PRId64"!\n", chunksize);
             return -1;
         }
         if (!memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) {