cluster/dht: Ignore ENOENT errors for unlink of linkfiles

If unlink of linkfile returns ENOENT, do not fail unlink.
Proceed with unlinking of cached file.

Change-Id: If7cec92b40c39d68dd9c3606c6c2c3a6bd67d27b
BUG: 966848
Signed-off-by: shishir gowda <sgowda@redhat.com>
Reviewed-on: http://review.gluster.org/4971
Reviewed-by: Amar Tumballi <amarts@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>
mgmt/glusterd: Set task op at the time of task-id set

Problem:
If a remove-brick start is executed on m1 with brick from m2
on local subvolume no rebalance process is launched. Because of
this volinfo->rebal.op is not set. This leads to volume status
failures.

Fix:
Set rebal.op even when the reblance process is not started.

Change-Id: I71c7e6f09353be14c1e8edca3c8685ebfdf226d6
BUG: 964059
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/5030
Reviewed-by: Kaushal M <kaushal@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
cluster/dht: Fix unused-but-set-variable warnings

Change-Id: Ie2b2dc54aa0d500c35752c72d3b562bcc05b1fc2
BUG: 969336
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/5123
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>