ctdb-tests: Remove statd-callout when running NFS tests

ctdb-tests: Remove statd-callout when running NFS tests

60.nfs backgrounds it so it persists in the background causing
problems.  In particular, it causes the "ctdb ip" command stub to be
run in parallel, which produces inconstent results.

Better not to run it at all in the NFS tests.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>
Autobuild-User(master): Martin Schwenke <martins@samba.org>
Autobuild-Date(master): Thu Jul  9 09:27:02 CEST 2015 on sn-devel-104