ostree-nspawn: Correctly shift initial root argument
ostree-nspawn: Correctly shift initial root argument

giuseppe/rpm-ostree,giuseppe/rpm-ostree,tmp-user/rpm-ostree,tmp-user/rpm-ostree,tmp-user/rpm-ostree,mdshuai/rpm-ostree,mdshuai/rpm-ostree,tmp-user/rpm-ostree,mdshuai/rpm-ostree,giuseppe/rpm-ostree,mdshuai/rpm-ostree,giuseppe/rpm-ostree