Remove remainders of --no-name-remapping option

Remove remainders of --no-name-remapping option

This option was removed in 2.5 (commit c3f565f059) but still showed
up in the ``openvpn --help`` text and in a Q&A section of the man page.

Change-Id: Ib15bd4148872db39a4c8291796a5da211bb20a87
Signed-off-by: Gert Doering <gert@greenie.muc.de>
Acked-by: Frank Lichtenheld <frank@lichtenheld.com>
Gerrit URL: https://gerrit.openvpn.net/c/openvpn/+/1411
Message-Id: <20251127115737.3598-1-gert@greenie.muc.de>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg34754.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>