ssh: T5841: Remove ssh-session-cleanup.service

With libpam-systemd >= 230-2, ssh-session-cleanup.service is no longer
necessary because when `UsePAM yes` in `/etc/ssh/sshd_config` (which is
the default), SSH sessions are cleaned up automatically when ssh-server
is shutdown or the system is rebooted.

data/live-build-config/hooks/live/18-enable-disable_services.chroot

@@ -76,7 +76,6 @@ systemctl disable dpkg-db-backup.service
 systemctl disable zabbix-agent2.service
 
 echo I: Enabling services
-systemctl enable ssh-session-cleanup.service
 systemctl enable vyos-hostsd.service
 systemctl enable acpid.service
 systemctl enable vyos-router.service

data/live-build-config/includes.chroot/lib/systemd/system/ssh-session-cleanup.service

@@ -1,13 +0,0 @@
-[Unit]
-Description=OpenBSD Secure Shell session cleanup
-Wants=network.target
-After=network.target
-
-[Service]
-ExecStart=/bin/true
-ExecStop=/usr/lib/openssh/ssh-session-cleanup
-RemainAfterExit=yes
-Type=oneshot
-
-[Install]
-WantedBy=multi-user.target

data/live-build-config/includes.chroot/usr/lib/openssh/ssh-session-cleanup

@@ -1,11 +0,0 @@
-#! /bin/sh
-
-ssh_session_pattern='sshd: \S.*@pts/[0-9]+'
-
-IFS="$IFS@"
-pgrep -a -f "$ssh_session_pattern" | while read pid daemon user pty; do
-	echo "Found ${daemon%:} session $pid on $pty; sending SIGTERM"
-	kill "$pid" || true
-done
-
-exit 0