Update Wayland notes on the Embedded Linux page

Qt Wayland is now part of the 5.4 release.

Change-Id: I7153d6bce72805a85b0205acdcae9bfe826b62fa
Reviewed-by: Louai Al-Khanji <louai.al-khanji@theqtcompany.com>
Reviewed-by: Robin Burchell <robin.burchell@viroteck.net>

doc/src/platforms/emb-linux.qdoc

@@ -365,9 +365,6 @@
   system; or more precisely, it is a protocol for clients to talk to a display
   server.
 
-  The Qt Wayland module is not currently part of Qt 5. Development snapshots can
-  be downloaded from the \l{http://qt.gitorious.org/qt/qtwayland}{Qt Wayland git
-  repository}. \note The sources checked out from the repository may have
-  dependencies on not-yet-released changes in Qt 5's qtbase and qtdeclarative
-  repositories.
+  The Qt Wayland module provides a \c wayland platform plugin that allows Qt
+  application to connect to a Wayland compositor.
 */