Remove Atmel FLIP from install scripts and documentation (#8822)

util/wsl_install.sh

@@ -31,21 +31,6 @@ source "$dir/win_shared_install.sh"
 
 pip3 install -r ${util_dir}/../requirements.txt
 
-pushd "$download_dir"
-while true; do
-    echo
-    echo "Flip need to be installed if you want to use that for programming."
-    echo "Please install it to the default location!"
-    read -p "Do you want to install it now? (Y/N) " res
-    case $res in
-        [Yy]* ) cmd.exe /c FlipInstaller.exe; break;;
-        [Nn]* ) break;;
-        * ) echo "Invalid answer";;
-    esac
-done
-popd
-
-
 echo 
 echo "Creating a softlink to the utils directory as ~/qmk_utils."
 echo "This is needed so that the the make system can find all utils it need."