dco-win: support for --persist-tun

dco-win: support for --persist-tun

Since version 0.8.0, dco-win driver added support for
DEL_PEER command, which enabled --persist-tun
implementation on client side.

Add real implementation for dco_del_peer on Windows,
which calls DEL_PEER, which clears peer state
on the driver without tearing tunnel down.

When pulled options are changed on restart,
we need to close and reopen tun device. This
is not yes supported for dco-win, so we close
tun and trigger reconnect.

Signed-off-by: Lev Stipakov <lev@openvpn.net>
Acked-by: Frank Lichtenheld <frank@lichtenheld.com>
Message-Id: <20220830104958.91-1-lstipakov@gmail.com>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg25136.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>