Systems - minor change to view to address warning during render...

prior to this change, rendering the _new partial would generate an
error similar to:

/git/katello/src/app/views/systems/_new.html.haml:15: warning: multiple values for a block parameter (0 for 1)
  from /usr/lib/ruby/gems/1.8/gems/haml-3.1.2/lib/haml/helpers/action_view_mods.rb:160

src/app/views/systems/_new.html.haml

@@ -12,7 +12,7 @@
     #{_("New system")}
     = content_for :content do
       #new_system
-        = form_tag({:action => "create"}, :id => "new_system_form") do |f|
+        = form_tag({:action => "create"}, :id => "new_system_form") do
           = hidden_field_tag 'system[environment_id]', @environment.id
           .grid_8#new_system
             %fieldset