tests/audiomatch: Add missing return code at the end of main()

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

tests/audiomatch.c

@@ -109,4 +109,6 @@ int main(int argc, char **argv) {
         }
     }
     printf("presig: %d postsig:%d c:%7.4f lenerr:%d\n", bestpos, datlen - siglen - bestpos, bestc / sigamp, datlen - siglen);
+
+    return 0;
 }