replace av_log(0, by av_log(NULL,

The first parameter is a pointer and NULL is more correct

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

ffmpeg_opt.c

@@ -2251,7 +2251,7 @@ static int opt_progress(void *optctx, const char *opt, const char *arg)
         arg = "pipe:";
     ret = avio_open2(&avio, arg, AVIO_FLAG_WRITE, &int_cb, NULL);
     if (ret < 0) {
-        av_log(0, AV_LOG_ERROR, "Failed to open progress URL \"%s\": %s\n",
+        av_log(NULL, AV_LOG_ERROR, "Failed to open progress URL \"%s\": %s\n",
                arg, av_err2str(ret));
         return ret;
     }