controllers: declare search_params helper in app controller.

app/controllers/application_controller.rb

@@ -1,5 +1,6 @@
 class ApplicationController < ActionController::Base
   include Pundit
+  helper_method :search_params
 
   class ApiLimitError < StandardError; end
 

app/controllers/bans_controller.rb

@@ -1,6 +1,5 @@
 class BansController < ApplicationController
   respond_to :html, :xml, :json
-  helper_method :search_params
 
   def new
     @ban = authorize Ban.new(permitted_attributes(Ban))

app/controllers/ip_bans_controller.rb

@@ -24,10 +24,4 @@ class IpBansController < ApplicationController
     @ip_ban.destroy
     respond_with(@ip_ban)
   end
-
-  private
-
-  def search_params
-    params.fetch(:search, {}).permit(%i[ip_addr order])
-  end
 end