coverity: Check return value from open
coverity: Check return value from open

Signed-off-by: Stéphane Graber <089afc6d81f66f1168a9849e15660feae286e024@ubuntu.com>
Acked-by: Serge E. Hallyn <3df611b026e4639bee8aef7a4beb2e39fcebb313@ubuntu.com>

virajs/lxc,ioops/lxc,weizhenwei/lxc,regit/lxc,regit/lxc,yubo/lxc,hallyn/lxc,rldleblanc/lxc,tych0/lxc,regit/lxc,armcc/lxc,rldleblanc/lxc,hfuCN/lxc,Ponce/lxc,hkjolhede/lxc,DarknessBeforeDawn/lxc,lazy404/lxc,yubo/lxc,caglar10ur/lxc,federicobriata/lxc,JohnPeacockMessageSystems/lxc,thmo/lxc,ecarrara/lxc,codebauss/lxc,sapun/lxc,sapun/lxc,JohnPeacockMessageSystems/lxc,codebauss/lxc,ioops/lxc,major/lxc,bmoar/lxc,lisongmin/lxc,ysbnim/lxc,GreatFruitOmsk/lxc,QingweiPeterLan/cs188-lxc,codebauss/lxc,ojkastl/lxc_Patches,lisongmin/lxc,ioops/lxc,efiop/lxc,bostjan/lxc,rowhit/lxc,ksperis/lxc,cjwatson/lxc,Distrotech/lxc,hfuCN/lxc,akshaykarle/lxc,bostjan/lxc,cjwatson/lxc,raspberrypython/lxc,ss1h2a3tw/lxc,efiop/lxc,tych0/lxc,aeris/lxc,aeris/lxc,ecarrara/lxc,Ponce/lxc,christiaan/lxc,rowhit/lxc,christiaan/lxc,lazy404/lxc,ojkastl/lxc_Patches,ecarrara/lxc,Distrotech/lxc,ojkastl/lxc_Patches,jirislaby/lxc,LynxChaus/lxc,armcc/lxc,akshaykarle/lxc,jirislaby/lxc,Pelagicore/lxc,hkjolhede/lxc,jirislaby/lxc,armcc/lxc,DarknessBeforeDawn/lxc,christiaan/lxc,hallyn/lxc,virajs/lxc,GreatFruitOmsk/lxc,tych0/lxc,DarknessBeforeDawn/lxc,szaszg/lxc,Ponce/lxc,szaszg/lxc,terceiro/lxc,Distrotech/lxc,ss1h2a3tw/lxc,hallyn/lxc,hkjolhede/lxc,ojkastl/lxc_Patches,caglar10ur/lxc,QingweiPeterLan/cs188-lxc,terceiro/lxc,bostjan/lxc,bmoar/lxc,caglar10ur/lxc,lazy404/lxc,terceiro/lxc,szaszg/lxc,cjwatson/lxc,LynxChaus/lxc,efiop/lxc,major/lxc,major/lxc,ksperis/lxc,weizhenwei/lxc,federicobriata/lxc,ss1h2a3tw/lxc,ysbnim/lxc,lisongmin/lxc,rowhit/lxc,yubo/lxc,LynxChaus/lxc,sapun/lxc,GreatFruitOmsk/lxc,hfuCN/lxc,weizhenwei/lxc,ksperis/lxc,federicobriata/lxc,Pelagicore/lxc,raspberrypython/lxc,Pelagicore/lxc,thmo/lxc,rldleblanc/lxc,thmo/lxc,akshaykarle/lxc,QingweiPeterLan/cs188-lxc,ysbnim/lxc,virajs/lxc,aeris/lxc,JohnPeacockMessageSystems/lxc,fwilson42/lxc,raspberrypython/lxc,fwilson42/lxc,bmoar/lxc,fwilson42/lxc