Add a link to the GPLv2 and a link to the LICENSE file in the
QEMU repository to fix the two TODO items in this appendix.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>