docs: say that the old repository is deprecated...

* docs/downloads.html.in: but will remain for sake of old links.

docs/downloads.html.in

@@ -74,9 +74,10 @@
     <p>
       Jim Mereying was maintaining a CVS to git mirror on
       <a href="http://git.et.redhat.com/?p=libvirt.git">git.et.redhat.com</a>.
-      Existing users should migrate to the new git server, as the
-      old one will be deprecated and turned into a mirror of the
-      libvirt.org one. It's available as:
+      Existing users should migrate to the new libvirt.org git server, as the
+      old one is now deprecated.  For the sake of old links including now-
+      rewritten SHA1s, we'll leave the old repository on-line for some time.
+      It is available as:
     </p>
     <pre>