s3:rpc_client fix a crash
state->cli->dc does not have to be set (e.g. when running
net rpc join against an older Samba PDC), so check it before dereferencing it
This fixes Bug 9669 - net rpc join crashes against a Samba 3.0.33 PDC
Bug: https://bugzilla.samba.org/show_bug.cgi?id=9669
Signed-off-by: Christian Ambach <ambi@samba.org>
Reviewed-by: Andreas Schneider <asn@samba.org>
Autobuild-User(master): Christian Ambach <ambi@samba.org>
Autobuild-Date(master): Wed Feb 20 19:00:52 CET 2013 on sn-devel-104