docs: redirected FAQ link to a new home provided by maintainer.

The original website is now gone.

docs.html

@@ -54,7 +54,7 @@
 	2.6 or does scanning only work as root? Read <a href="README.linux">README.linux</a>.
       </li>
       <li>
-	<a href="http://www.xs4all.nl/~ljm/SANE-faq.html" target="_top">Frequently Asked Questions
+	<a href="https://dullaart.website/sane" target="_top">Frequently Asked Questions
 	(FAQ)</a>: The SANE FAQ was originally created by Nicolas de Peslouan and is now maintained
 	by <a href="mailto:ljm@xs4all.nl">ljm Dullaart</a>.
       </li>