init: become session leader
init: become session leader

Before exec()ing we need to become session leader otherwise some shells will
not be able to correctly initialize job control.

Signed-off-by: Christian Brauner <48455ab3070520a2d174545c7239d6d0fabd9a83@ubuntu.com>

caglar10ur/lxc,terceiro/lxc,hallyn/lxc,caglar10ur/lxc,hallyn/lxc,thmo/lxc,caglar10ur/lxc,terceiro/lxc,terceiro/lxc,ss1h2a3tw/lxc,ss1h2a3tw/lxc,hallyn/lxc,thmo/lxc,ss1h2a3tw/lxc,thmo/lxc