suback parse wrong if resonCode bigger than 128

[lijiahao007]

extension FrameSubAck: InitialWithBytes {
    
    init?(packetFixedHeaderType: UInt8, bytes: [UInt8]) {
        
        self.packetFixedHeaderType = packetFixedHeaderType

        var protocolVersion = "";
        if let storage = CocoaMQTTStorage() {
            protocolVersion = storage.queryMQTTVersion()
        }

        if (protocolVersion == "5.0"){
            // the bytes length must bigger than 3
            guard bytes.count >= 4 else {
                return nil
            }

            self.msgid = UInt16(bytes[0]) << 8 + UInt16(bytes[1])
            self.grantedQos = []
            for i in 3 ..< bytes.count {
                guard let qos = CocoaMQTTQoS(rawValue: bytes[i]) else {
                    return nil
                }
                self.grantedQos.append(qos)
            }

            self.reasonCodes = [CocoaMQTTSUBACKReasonCode]()
            for i in 3 ..< bytes.count {
                guard let qos = CocoaMQTTSUBACKReasonCode(rawValue: bytes[i]) else {
                    return nil
                }
                self.reasonCodes! += [qos]
            }

            self.subAckProperties = MqttDecodeSubAck()
            self.subAckProperties!.decodeSubAck(fixedHeader: packetFixedHeaderType, pubAckData: bytes)

        }else{
            // the bytes length must bigger than 3
            guard bytes.count >= 3 else {
                return nil
            }

            self.msgid = UInt16(bytes[0]) << 8 + UInt16(bytes[1])
            self.grantedQos = []
            for i in 2 ..< bytes.count {
                guard let qos = CocoaMQTTQoS(rawValue: bytes[i]) else {
                    return nil
                }
                self.grantedQos.append(qos)
            }

        }
        
    }
}

if bytes is [0, 1, 0, 135], this function return nil。Because CocoaMQTTQoS(rawValue: bytes[i]) return nil

[lijiahao007]

Does not seem to respond correctly to the following situation