When `lxc.autodev = 0` and empty tmpfs is mounted on /dev
and private pts are requested, we need to ensure '/dev/pts'
exists before attempting to mount devpts on it.
Signed-off-by: Jean-Tiare LE BIGOT <jean-tiare.le-bigot@ovh.net>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>