lavu/log: do not skip overwritten lines.

If the line ends with \r, it will not flood the tty, and
the "Last message repeated" line would overwrite it.
Fix bug introduced by c25d1ba5.

libavutil/log.c

@@ -224,7 +224,8 @@ void av_log_default_callback(void* ptr, int level, const char* fmt, va_list vl)
         is_atty = isatty(2) ? 1 : -1;
 #endif
 
-    if (print_prefix && (flags & AV_LOG_SKIP_REPEATED) && !strcmp(line, prev) && *line){
+    if (print_prefix && (flags & AV_LOG_SKIP_REPEATED) && !strcmp(line, prev) &&
+        *line && line[strlen(line) - 1] != '\r'){
         count++;
         if (is_atty == 1)
             fprintf(stderr, "    Last message repeated %d times\r", count);