container: daemonize implies close_all_fds too

Daemonize implies also --close-all-fds, that means if we are using
SetDaemonize(), it should also invoke SetCloseAllFds().

See:

https://github.com/lxc/lxc/blob/master/src/lxc/lxc_start.c#L99

Also SetCloseAllFds() is invoked after SetDaemonize(), see:

https://github.com/lxc/lxc/blob/master/src/lxc/lxc_start.c#L252 // Daemonize
https://github.com/lxc/lxc/blob/master/src/lxc/lxc_start.c#L264 // CloseAllFDs