fix NULL dereference
fix NULL dereference

lxc_console dereferences C, so we should check that it is not null and fail if
it is.

Reported-by: Coverity
Signed-off-by: Tycho Andersen <10c18fcb898ee6b17d6575d444b125d10b3f4d6a@canonical.com>
Acked-by: Serge E. Hallyn <3df611b026e4639bee8aef7a4beb2e39fcebb313@ubuntu.com>

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