driver.rb: unused variable

* benchmark/driver.rb (BenchmarkDriver.load): remove unused
  variable.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@54064 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

benchmark/driver.rb

@@ -31,7 +31,6 @@ class BenchmarkDriver
   end
 
   def self.load(input, type, opt)
-    attrs = [:executables, :results]
     case type
     when 'yaml'
       require 'yaml'