docs/website/support.html: document how to join irc channel from matrix

Signed-off-by: Marcus Hoffmann <buildroot@bubu1.eu>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

docs/website/support.html

@@ -21,7 +21,9 @@
 		<div class="col-sm-11">
 		  <p>The Buildroot IRC channel is <a href="irc://irc.oftc.net/#buildroot">
 		      #buildroot</a>, hosted on OFTC. If you do not have an IRC client, you can
-		    use the <a href="https://www.oftc.net/WebChat/">OFTC web interface</a>.
+		    use the <a href="https://www.oftc.net/WebChat/">OFTC web interface</a>. The
+		    channel is also bridged to matrix as <a href="https://matrix.to/#/#_oftc_#buildroot:matrix.org">
+		      #_oftc_#buildroot:matrix.org</a>.
 		    When asking for help on IRC, share relevant logs or pieces of code using a code
 		    sharing website.</p>