[Help document bug] For pngfix, the help document misses some options

[ccccmd]

The help document of pngfix misses the option "debug" and "verbose" for version 1.6.37.

• For the option "debug", the following code appears during option parsing and modifies the global.errors, global.warnings, global.quiet and global.verbose in ./contrib/tools/pngfix.c:3875-3880 for version 1.6.37.

      {
         /* To help debugging problems: */
         global.errors = global.warnings = 1;
         global.quiet = 0;
         global.verbose = 7;
      }

• For the option "verbose", the following code appears during option parsing and modifies the global.verbose in ./contrib/tools/pngfix.c:3947 for version 1.6.37.

         ++global.verbose;

But they do not appear in the help document.

It may prevent users from using the relevant function. Meanwhile, while both options are auxiliary options, it may aslo exist security problems.