replaced fmt.Sprintf with strconv.Itoa for Protocol.String()
replaced fmt.Sprintf with strconv.Itoa for Protocol.String()

j-kato/gobgp,a16/gobgp,a16/gobgp,a16/gobgp,j-kato/gobgp,a16/gobgp,fujita/gobgp,j-kato/gobgp,a16/gobgp,fujita/gobgp,fujita/gobgp,osrg/gobgp,a16/gobgp,a16/gobgp,fujita/gobgp,osrg/gobgp,osrg/gobgp,osrg/gobgp