Remove integration type without container manager from container integration

Remove integration type without container manager from container integration

Existing container integration was supporing with container-manager and
without container-manager integration.  After the scarthgap update,
systemd cgroup-v1 and v2 mixed support was disabled.  It require to big
rework in resource controle feature.

The lxc only integration (without container-manager integration) has some
limitation for device support.  For example, it can't handle dynamic
device/network interface change, it' can't protect device access from
guest using mknod.  On the other hand, if I mantain to this integration,
it need many human resource.  The lxc only integration does not have
value for these work.

This change aim to maintain document.

Bug-AGL: SPEC-5283

Change-Id: I2c89e243538bcdb73ec4ee9adb5d28a4ec99f9ff
Signed-off-by: Naoto Yamaguchi <naoto.yamaguchi@aisin.co.jp>
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/documentation/+/30513
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>
Tested-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>