Change Ie548f7216610e15af24c96f65a58cc8de603235c introduced a new
parameter, SshFirewallAllowAll, set to True by default.
This parameter allows to add a generic firewall rule allowing, as
its name states, world access to the SSH service.
Until now, if someone changes his mind and decides to deactivate
this opening, the rule will not be removed, although the operator
sets the variable to False.
This patch intends to reflect the operator will regarding ssh access.
Change-Id: I1b4e23b602cf9c41ce6f9a1b602359d7aa7224c0