CHJ: fix warnings and reformat

Author: sipma

CodeHawk/CHJ/jchpre/jCHBcPattern.ml

@@ -5,6 +5,7 @@
    The MIT License (MIT)
  
    Copyright (c) 2005-2020 Kestrel Technology LLC
+   Copyright (c) 2020-2024 Henny B. Sipma
 
    Permission is hereby granted, free of charge, to any person obtaining a copy
    of this software and associated documentation files (the "Software"), to deal