Correct documentation for --ns-cert-type

Correct documentation for --ns-cert-type

Our documentation claimed this option was removed.
But it was not, for compatiblity reasons. So reflect
the correct status.

Change-Id: I1d1851eaebe8bf66c92dac3c8c10f68b1ec3ef33
Signed-off-by: Frank Lichtenheld <frank@lichtenheld.com>
Acked-by: Gert Doering <gert@greenie.muc.de>
Gerrit URL: https://gerrit.openvpn.net/c/openvpn/+/1428
Message-Id: <20251210085625.32174-1-gert@greenie.muc.de>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg34984.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>