Move dco_installed back to link_socket from link_socket.info.actual

Move dco_installed back to link_socket from link_socket.info.actual

this change was done in order to be able to differentiate when needing to
use dco and when to use normal socket sendto. Since we want to eventually
completely use the userspace sockets for sending/receiving, we just switch
to always use UDP sendto even if the socket is already installed in the
kernel.

Signed-off-by: Arne Schwabe <arne@rfc2549.org>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <20221224194253.3202231-4-arne@rfc2549.org>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg25792.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>
(cherry picked from commit 1413b38d0eacafb6c03c701236fe546f44f39a8d)