Merge pull request #180 from dev-sec/fix_sysctl_ipv6

fix wrong sysctl

Author: schurzi

controls/sysctl_spec.rb

@@ -314,7 +314,7 @@
   describe kernel_parameter('net.ipv6.conf.default.autoconf') do
     its(:value) { should eq 0 }
   end
-  describe kernel_parameter('net.ipv6.all.default.autoconf') do
+  describe kernel_parameter('net.ipv6.conf.all.autoconf') do
     its(:value) { should eq 0 }
   end
 end