If the user defines a $max_timeout of 30, the service will wait 30 seconds
before it considers lxc-stop complete even though lxc-stop might actually
finish much sooner.  This introduces an unneeded delay.

This commit changes the behavior to check once per second to see when lxc-stop
actually stops doing so up to $max_timeout.  It also slightly simplifies the
code with logic to append the -t $max_timeout to the script.

Signed-off-by: John Audia <graysky@archlinux.us>

Signed-off-by: Martin Hammer <34623636+hammer-is@users.noreply.github.com>
Signed-off-by: martin <martin@DESKTOP-C822DHJ.lan>

Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Signed-off-by: Marijan Svalina <marijan.svalina@sartura.hr>
Signed-off-by: Luka Perkov <luka.perkov@sartura.hr>

Standard LXC autostart is currently not working in OpenWrt,
therefore add our own autostart mechanism for now.

Signed-off-by: Daniel Dickinson <openwrt@daniel.thecshore.com>