LU-1287 mountconf: write failover nid config correctly

LU-1287 mountconf: write failover nid config correctly

Once OST starts before MDT, MDT needs steal OSC config from client
config, but both target nids and failover nids are stored as the
same type of config LCFG_ADD_UUID. To handle this correctly, all
LCFG_ADD_UUID before LCFG_SETUP is treated as target nids, while
after as failover nids. NB this implies that records should be
written into config file in fixed order.

Signed-off-by: Lai Siyao <laisiyao@whamcloud.com>
Change-Id: I42d014911edad1bc53bb1a66def160ee0da3e670
Reviewed-on: http://review.whamcloud.com/3107
Reviewed-by: Sebastien Buisson <sebastien.buisson@bull.net>
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>