[InterNetNews/inn] 014294: nntpget: Remove obsolete -d flag

[Julien ÉLIE]

  Branch: refs/heads/main
  Home:   https://github.com/InterNetNews/inn
  Commit: 014294b0ecba45610b5f29942c0dbed22ca090b3
      https://github.com/InterNetNews/inn/commit/014294b0ecba45610b5f29942c0dbed22ca090b3
  Author: Julien ÉLIE <Julien-Elie at users.noreply.github.com>
  Date:   2021-12-04 (Sat, 04 Dec 2021)

  Changed paths:
    M backends/nntpget.c
    M doc/pod/nntpget.pod

  Log Message:
  -----------
  nntpget: Remove obsolete -d flag

It is used to specify a list of distributions in the NEWNEWS command
but this command does not expect such a list.