configure: Fix wrong reference to user support mailing list

configure

@@ -329,7 +329,7 @@ die(){
 
 If you think configure made a mistake, make sure you are using the latest
 version from Git.  If the latest version fails, report the problem to the
-libav-user@libav.org mailing list or IRC #libav on irc.freenode.net.
+libav-tools@libav.org mailing list or IRC #libav on irc.freenode.net.
 EOF
     if disabled logging; then
         cat <<EOF