Update IRC network to Libera.Chat

The `#glfw` IRC channel is moving to the Libera.Chat network due to the
recent takeover of the Freenode network.

README.md

@@ -249,7 +249,7 @@ well as news, documentation and other information about the project.
 
 If you have questions related to the use of GLFW, we have a
 [forum](https://discourse.glfw.org/), and the `#glfw` IRC channel on
-[Freenode](http://freenode.net/).
+[Libera.Chat](https://libera.chat/).
 
 If you have a bug to report, a patch to submit or a feature you'd like to
 request, please file it in the

docs/CONTRIBUTING.md

@@ -24,7 +24,7 @@ section](https://discourse.glfw.org/c/support) of the forum, under the [Stack
 Overflow tag](https://stackoverflow.com/questions/tagged/glfw) or [Game
 Development tag](https://gamedev.stackexchange.com/questions/tagged/glfw) on
 Stack Exchange or in the IRC channel `#glfw` on
-[Freenode](http://freenode.net/).
+[Libera.Chat](https://libera.chat/).
 
 Questions about the design or implementation of GLFW or about future plans
 should be asked in the [dev section](https://discourse.glfw.org/c/dev) of the

docs/SUPPORT.md

@@ -5,7 +5,7 @@ guides and the API reference.
 
 If you have questions about using GLFW, we have a
 [forum](https://discourse.glfw.org/), and the `#glfw` IRC channel on
-[Freenode](http://freenode.net/).
+[Libera.Chat](https://libera.chat/).
 
 Bugs are reported to our [issue tracker](https://github.com/glfw/glfw/issues).
 Please check the [contribution