vm_eval.c: omit klass

* vm_eval.c (rb_search_method_entry): also Qfalse and Qnil are
  immediate values, so have no RBASIC.  omit klass, which is 0.

git-svn-id: svn+ssh://svn.ruby-lang.org/ruby/trunk@44760 b2dd03c8-39d4-4d8f-98ff-823fe69b080e