etcdmain: use embed.DefaultLogOutput for flags
etcdmain: use embed.DefaultLogOutput for flags

Signed-off-by: Gyu-Ho Lee <3454051ee3341eb69bdf6fca40899cdad4d86496@gmail.com>

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