Focusrite2i2g4_drivers.md: use make install instead of custom .desktop file

Removed instructions for adding a .desktop file and emphasized running 'make install' to create it.

Author: jan-revay

CommonInitScripts/Focusrite2i2g4_drivers.md

@@ -6,19 +6,4 @@
 4. Read the docs:
    - <https://github.com/geoffreybennett/alsa-scarlett-gui/blob/master/docs/iface-4th-gen-small.md>
    - <https://github.com/geoffreybennett/alsa-scarlett-gui/blob/master/docs/USAGE.md>
-5. Add .desktop file:
-   - `cd ~/.local/share/applications`
-   - `v alsa-scarlett-gui.desktop`
-   - `chmod +x alsa-scarlett-gui.desktop`
-   - ```
-      [Desktop Entry]
-      Name=Focusrite Control
-      Comment=Open ALSA Scarlett GUI for Focusrite interfaces
-      Exec=sh -c "cd /home/jr/x/alsa-scarlett-gui/src/ && ./alsa-scarlett-gui"
-      Icon=audio-card
-      Terminal=false
-      Type=Application
-      Categories=AudioVideo;Mixer;Settings;
-      StartupNotify=true
-      StartupWMClass=vu.b4.alsa-scarlett-gui
-      ```
+5. Don't forget to run `make install` to create the .desktop file