babel: allow nat64 prefix

roles/install_babeld/templates/babeld.conf.j2

@@ -41,6 +41,7 @@ reflect-kernel-metric true
 in ip 10.222.0.0/16 allow
 in ip 2a03:2260:1016::/48 allow
 in ip 2003:46:e028::/48 allow # finzelberg
+in ip 64:ff9b::/96 allow # nat64
 in ip fd62:44e1:da::/48 allow
 in deny # ignore default routes on uplinks
 {% endif %}
@@ -57,6 +58,7 @@ redistribute if {{ peer.name }} metric 128
 # all local addresses
 redistribute ip 10.222.0.0/16 allow
 redistribute ip 2a03:2260:1016::/48 allow
+redistribute ip 64:ff9b::/96 allow
 redistribute ip fd62:44e1:da::/48 allow
 redistribute local deny