A máš to nainstalované v systému?
$ apt-cache search qt serial port
cutecom - Graphical serial terminal, like minicom
libqt5extserialport-dbg - interface to serial ports for Qt-based applications, debug info
libqt5extserialport-dev - interface to serial ports for Qt-based applications
libqt5extserialport1 - interface to serial ports for Qt-based apps - development files
libqt5serialport5 - Qt 5 serial port support
libqt5serialport5-dev - Qt 5 serial port development files
libqtsolutions-soap-2.7-1 - Basic web service support - SOAP protocol
python-pyqt5.qtserialport - Python 2 bindings for QtSerialPort module
python-pyqt5.qtserialport-dbg - Python 2 bindings for QtSerialPort module (debug extension)
python3-pyqt5.qtserialport - Python 3 bindings for QtSerialPort module
python3-pyqt5.qtserialport-dbg - Python 3 bindings for QtSerialPort module (debug extension)
qtserialport5-dbg - Qt 5 serial port library debugging symbols
qtserialport5-doc - Qt 5 serial port documentation
qtserialport5-doc-html - Qt 5 serial port HTML documentation
=>
sudo apt-get install libqt5serialport5{,-dev}