Fix NoSuchOptError when using use_floatingip_for_ssh

It looks like a non-existent option is referenced and
this breaks the Grenade Neutron job. This patch should
put everything back to normal.

Closes-bug: #1432091

Change-Id: Iff7f4523a2dd370e4b6c3724ac98cfc7203ceb26
1 file changed