tests/bugs/bug-762989.t: do not check the listening ports

Change-Id: Ifbcf28bb476ee95343beaf42fb84a1b834c9ffcb
BUG: 762989
Signed-off-by: Raghavendra Bhat <raghavendra@redhat.com>
Reviewed-on: http://review.gluster.org/4486
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>