e2e: Fix govet errors
e2e: Fix govet errors

xiang90/etcd,etcd-io/etcd,li-ang/etcd,sebrandon1/etcd,ajityagaty/etcd,rnaveiras/etcd,fanminshi/etcd,sinsharat/etcd,gyuho/etcd,ajityagaty/etcd,whuwxl/etcd,joshix/etcd,mqliang/etcd,gyuho/etcd,vimalk78/etcd,rnaveiras/etcd,joshix/etcd,lorneli/etcd,whuwxl/etcd,rnaveiras/etcd,mkumatag/etcd,li-ang/etcd,cockroachdb/etcd,glevand/coreos--etcd,xiang90/etcd,etcd-io/etcd,sinsharat/etcd,dannysauer/etcd,bdarnell/etcd,dannysauer/etcd,heyitsanthony/etcd,coreos/etcd,mqliang/etcd,coreos/etcd,heyitsanthony/etcd,cockroachdb/etcd,fanminshi/etcd,lorneli/etcd,ajityagaty/etcd,vimalk78/etcd,mkumatag/etcd,glevand/coreos--etcd,mkumatag/etcd,etcd-io/etcd,sebrandon1/etcd,mqliang/etcd,bdarnell/etcd