sp: remove automatic storage pool reconnection

On startup the storage pool directory (/rhev/data-center/<spUUID>)
is removed by __cleanStorageRepository preventing the automatic
reconnection (_connectStoragePool) from actually taking place.
Since vdsm has been running for quite some time (years) without the
automatic reconnection we can safely remove it.

Change-Id: Ia57afc04db02b6c15633d09349a55b3ff5ae7fda
Signed-off-by: Federico Simoncelli <fsimonce@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/21424
Reviewed-by: Dan Kenigsberg <danken@redhat.com>