For MacOSX SerialPortInfo class if you can not get the information - instead of empty string adds an "Unknown".
For MacOSX SerialPortInfo class if you can not get the information -
instead of empty string adds an "Unknown".

kobolabs/qtserialport,kobolabs/qtserialport,RoadWorksSoftware/QtSerialPort-OS2,RoadWorksSoftware/QtSerialPort-OS2