use enum type instead of int

git-svn-id: file:///var/local/repositories/ffmpeg/trunk@13089 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavformat/matroskadec.c

@@ -58,7 +58,7 @@ typedef struct Track {
     MatroskaTrackFlags flags;
 
     int encoding_scope;
-    int encoding_algo;
+    MatroskaTrackEncodingCompAlgo encoding_algo;
     uint8_t *encoding_settings;
     int encoding_settings_len;
 } MatroskaTrack;