bug#26820: 26.0.50; DNS mode and IPv6 reverse zones

[Glenn Morris]

Thanks, but:
    
    In dns-mode-reverse-and-expand-ipv6:
    ~/dns-mode.el:330:41:Warning: reference to free variable ‘with’
    ~/dns-mode.el:330:46:Warning: reference to free variable ‘filler-done’
    ~/dns-mode.el:330:58:Warning: reference to free variable ‘=’
    ~/dns-mode.el:331:41:Warning: reference to free variable ‘for’
    ~/dns-mode.el:331:45:Warning: reference to free variable ‘chunk’
    ~/dns-mode.el:331:51:Warning: reference to free variable ‘in’
    ~/dns-mode.el:332:41:Warning: reference to free variable ‘if’
    ~/dns-mode.el:334:41:Warning: reference to free variable ‘append’
    ~/dns-mode.el:335:58:Warning: reference to free variable ‘repeat’
    ~/dns-mode.el:336:58:Warning: reference to free variable ‘collect’
    ~/dns-mode.el:337:56:Warning: assignment to free variable ‘filler-done’
    ~/dns-mode.el:338:41:Warning: reference to free variable ‘else’
    ~/dns-mode.el:346:17:Warning: reference to free variable ‘char’
    ~/dns-mode.el:346:22:Warning: reference to free variable ‘across’
    ~/dns-mode.el:347:13:Warning: reference to free variable ‘do’
    
    In end of data:
    ~/dns-mode.el:360:1:Warning: the following functions are not known to be
        defined: loop, minusp

which is due to using stuff from cl.el without requiring it.
And in any case, the cl-lib versions should be used instead these days.
Please could you revise that? TIA.