Remove topic for enabling VirGL

VirGL is going to be enabled by default since 1.22
and there will be no necessity to enable it
explicitly. Hence this commit removes the topic
that was added earlier to enable VirGL.

howto/anbox/landing.md

@@ -4,4 +4,3 @@ The following guides are available:
 
 * [How to develop a platform plugin](https://discourse.ubuntu.com/t/how-to-develop-a-platform-plugin/33099)
 * [How to develop an addon](https://discourse.ubuntu.com/t/develop-and-test-addons-in-development-mode/36914)
-* [How to enable support for VirGL](https://discourse.ubuntu.com/t/how-to-enable-virgl/42426)

index.md

@@ -118,7 +118,6 @@ Thinking about using Anbox Cloud for your next project? [Get in touch!](https://
 | 2 | howto/anbox/landing | [Work with the Anbox runtime](https://discourse.ubuntu.com/t/how-to-work-with-the-anbox-runtime/33098) |
 | 3 | howto/anbox/develop-platform | [Develop a platform plugin](https://discourse.ubuntu.com/t/how-to-develop-a-platform-plugin/33099) |
 | 3 | howto/anbox/develop-addon | [Develop and test addons](https://discourse.ubuntu.com/t/develop-and-test-addons-in-development-mode/36914) |
-| 3 | howto/anbox/enable-virgl | [Enable VirGL](https://discourse.ubuntu.com/t/how-to-enable-virgl/42426) |
 | 2 | howto/android/landing | [Work with Android](https://discourse.ubuntu.com/t/how-to-work-with-android-in-anbox-cloud/42428) |
 | 3 | howto/android/graphics-debugging-with-renderdoc | [Graphics debugging with Renderdoc](https://discourse.ubuntu.com/t/how-to-debug-graphics-with-renderdoc/42427) |
 | 2 | howto/troubleshoot/landing | [Troubleshoot Anbox Cloud](https://discourse.ubuntu.com/t/how-to-troubleshoot-anbox-cloud/17837)|