Fix another Windows build issue.

Author: michaelrsweet

htmldoc/mmd.c

@@ -1223,7 +1223,7 @@ mmdLoadString(mmd_t *root,	/* I - Root node for document or `NULL` for a n
  if ((fp = fopen(tempfile, "w+")) == NULL)
  return (root);
 
- fputs(fp, s);
+ fputs(s, fp);
  rewind(fp);
 
 #else // POSIX