LU-560 Fixup intent status on ENOENT in mdt_intent_reint

LU-560 Fixup intent status on ENOENT in mdt_intent_reint

Clear -ENOENT from rep->lock_policy_res2 for non existent files so
that clients may cache negative dentries if they hold
MDS_INODELOCK_UPDATE on the parent directory.

Change-Id: I238f1001782923a595f9f7ee1c094d53ab1422ae
Signed-off-by: John Hammond <jhammond@tacc.utexas.edu>
Reviewed-on: http://review.whamcloud.com/1173
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Johann Lombardi <johann@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>