removing -s option from gswauth tools

the --suffix option is not currently supported in this version
of gswauth, so we are removing to not confuse users.

Bug 1262230: https://bugs.launchpad.net/gluster-swift/+bug/1262230

Change-Id: I12da2aad5929f619f838c217330bef503b7e0ba2
Signed-off-by: Thiago da Silva <thiago@redhat.com>
Reviewed-on: http://review.gluster.org/6542
Reviewed-by: pushpesh sharma <psharma@redhat.com>
Tested-by: pushpesh sharma <psharma@redhat.com>
Reviewed-by: Prashanth Pai <ppai@redhat.com>
Tested-by: Prashanth Pai <ppai@redhat.com>
Reviewed-by: Chetan Risbud <crisbud@redhat.com>
Reviewed-on: http://review.gluster.org/6660
Tested-by: Chetan Risbud <crisbud@redhat.com>