glusterd: Removed start-unlock event injection in 'synctask' codepath

Change-Id: I87e02c95d0b650dab7f9ee86c96b2e09ada50109
BUG: 862834
Signed-off-by: Krishnan Parthasarathi <kparthas@redhat.com>
Reviewed-on: http://review.gluster.org/4118
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Amar Tumballi <amarts@redhat.com>
Reviewed-by: Anand Avati <avati@redhat.com>