lxc/restore: Fix typo in help
lxc/restore: Fix typo in help

Signed-off-by: Qu Junping <4e8c2f9ccb08322f300a7fde0ed05d759399969f@gmail.com>

atxwebs/lxd,lxc/lxd,stgraber/lxd,stgraber/lxd,hallyn/lxd,lxc/lxd,hallyn/lxd,stgraber/lxd,lxc/lxd,stgraber/lxd,lxc/lxd,atxwebs/lxd,atxwebs/lxd,stgraber/lxd,hallyn/lxd,stgraber/lxd,stgraber/lxd,lxc/lxd,hallyn/lxd,atxwebs/lxd,hallyn/lxd,hallyn/lxd,lxc/lxd,lxc/lxd