Fix typo

Author: tekknolagi

benchmarks/attr_accessor.rb

@@ -6,7 +6,7 @@ class TheClass
   def initialize
     @v0 = 1
     @v1 = 2
-    @v3 = 3
+    @v2 = 3
     @levar = 1
   end
 

benchmarks/getivar.rb

@@ -4,7 +4,7 @@ class TheClass
   def initialize
     @v0 = 1
     @v1 = 2
-    @v3 = 3
+    @v2 = 3
     @levar = 1
   end