doc: Add packages that provide Qt Wayland plugin for Linux

Author: hebasto

doc/build-unix.md

@@ -122,6 +122,10 @@ To build with Qt 5 you need the following:
 
     sudo apt-get install libqt5gui5 libqt5core5a libqt5dbus5 qttools5-dev qttools5-dev-tools
 
+Additionally, to support Wayland protocol for modern desktop environments:
+
+    sudo apt install qtwayland5
+
 libqrencode (optional) can be installed with:
 
     sudo apt-get install libqrencode-dev
@@ -181,6 +185,10 @@ To build with Qt 5 you need the following:
 
     sudo dnf install qt5-qttools-devel qt5-qtbase-devel
 
+Additionally, to support Wayland protocol for modern desktop environments:
+
+    sudo dnf install qt5-qtwayland
+
 libqrencode (optional) can be installed with:
 
     sudo dnf install qrencode-devel