modify for creating ssh key for root

generate_ssh_keys.rb

define :generate_ssh_keys, :user_account => nil do
  username = params[:user_account]

  raise ":user_account should be provided." if username.nil?

  Chef::Log.debug("generate ssh key for #{username}.")

  execute "generate ssh key for #{username}." do
    user username
    creates "#{(username != 'root' ? '/home' : '')}/#{username}/.ssh/id_rsa.pub"
    command "ssh-keygen -t rsa -q -f #{(username != 'root' ? '/home' : '')}/#{username}/.ssh/id_rsa -P \"\""
  end
end