Remove the "hardening" menu frm bsdinstall

[allanjude]

Summary

If these options should be enabled, the defaults should be changed so
that installs done with the installer do not differ from a default
build.

[jhb]

I'm would be fine with just removing it from the default install flow but leaving it around if a user wants to go look at it. I'm also fine with axing it entirely as this does. I would be less of a fan of changing some of these behaviors by default.