lxc-ls: use fewer syscalls when doing ipc
lxc-ls: use fewer syscalls when doing ipc

Signed-off-by: Christian Brauner <48455ab3070520a2d174545c7239d6d0fabd9a83@mailbox.org>

hfuCN/lxc,ss1h2a3tw/lxc,QingweiPeterLan/cs188-lxc,aeris/lxc,ysbnim/lxc,GreatFruitOmsk/lxc,ysbnim/lxc,hallyn/lxc,LynxChaus/lxc,ss1h2a3tw/lxc,thmo/lxc,thmo/lxc,LynxChaus/lxc,ss1h2a3tw/lxc,terceiro/lxc,terceiro/lxc,federicobriata/lxc,thmo/lxc,QingweiPeterLan/cs188-lxc,GreatFruitOmsk/lxc,hallyn/lxc,aeris/lxc,LynxChaus/lxc,terceiro/lxc,cjwatson/lxc,GreatFruitOmsk/lxc,caglar10ur/lxc,QingweiPeterLan/cs188-lxc,federicobriata/lxc,hallyn/lxc,ysbnim/lxc,cjwatson/lxc,hfuCN/lxc,aeris/lxc,caglar10ur/lxc,caglar10ur/lxc,hfuCN/lxc,federicobriata/lxc,cjwatson/lxc