remove qt support

recipes-core/base-files/base-files_%.bbappend

@@ -3,7 +3,7 @@ hostname = "diya"
 do_install:append () {
     cat << 'EOF' >> "${D}${sysconfdir}/profile"
 # QT related setting
-export QT_QPA_PLATFORM=wayland-egl
+export GDK_BACKEND=wayland
 export XDG_RUNTIME_DIR=/home/$USER/.xdg
 export PATH=$PATH:/home/$USER/bin
 if [ ! -e "$XDG_RUNTIME_DIR" ]; then