doc: Do not have examples with accept-all in our repository

We do not want to tell random users to run a network with the
accept-all. This was pointed out by Katerina.
diff --git a/openbsc/doc/examples/osmo-nitb/nokia/openbsc_nokia_3trx.cfg b/openbsc/doc/examples/osmo-nitb/nokia/openbsc_nokia_3trx.cfg
index a7d980f..f4c715c 100644
--- a/openbsc/doc/examples/osmo-nitb/nokia/openbsc_nokia_3trx.cfg
+++ b/openbsc/doc/examples/osmo-nitb/nokia/openbsc_nokia_3trx.cfg
@@ -13,7 +13,6 @@
  mobile network code 1
  short name OpenBSC
  long name OpenBSC
- auth policy accept-all
  timer t3101 10
  timer t3113 60
  bts 0