script/priv-net-run: improve shebang compatibility
script/priv-net-run: improve shebang compatibility

aanm/cni,squaremo/cni,achanda/cni,tangle329/cni,murat1985/cni,jonboulle/cni,aanm/cni,dcbw/cni,mcastelino/cni,tomdee/cni,tomdee/cni,appc/cni,luxas/cni,squaremo/cni,mcastelino/cni,containernetworking/plugins,containernetworking/plugins,rosenhouse/cni,dcbw/cni,steveeJ/cni,squeed/plugins,luxas/cni,murat1985/cni,tangle329/cni,achanda/cni,containernetworking/cni,kad/cni,jonboulle/cni,steveeJ/cni,squeed/plugins,containernetworking/cni,rosenhouse/cni,kad/cni,appc/cni