pppoe: Allow setting for ppp-interface in pillar.

Signed-off-by: Maximilian Wilhelm <max@rfc2324.org>

pppoe/tkom_peer.tmpl

@@ -18,7 +18,8 @@ user "{{ user }}"
 # This line should work fine if this computer is the only one accessing
 # the Internet through this DSL connection. This is the right line to use
 # for most people.
-pty "/usr/sbin/pppoe -I vlan4006 -T 80 -m 1452"
+{%- set iface = salt['pillar.get']('nodes:' ~ grains['id'] ~ ':pppoe:iface', 'eth2') %}
+pty "/usr/sbin/pppoe -I {{ iface }} -T 80 -m 1452"
 
 # An even more conservative version of the previous line, if things
 # don't work using -m 1452...