cluster/dht: Added keys in dht_lookup_everywhere_done

Case where both cached  (C1)  and hashed file are found,
but hash does not point to above cached node (C1), then
dont unlink if either fd-is-open on hashed or
linkto-xattr is not found.

Change-Id: I7ef49b88d2c88bf9d25d3aa7893714e6c0766c67
BUG: 1138385
Signed-off-by: Venkatesh Somyajulu <vsomyaju@redhat.com>

Change-Id: I86d0a21d4c0501c45d837101ced4f96d6fedc5b9
Signed-off-by: Venkatesh Somyajulu <vsomyaju@redhat.com>
Reviewed-on-master: http://review.gluster.org/8429
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: susant palai <spalai@redhat.com>
Reviewed-by: Raghavendra G <rgowdapp@redhat.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>
Reviewed-on: http://review.gluster.org/8607
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>