proc.c: fix arity of rest keywords argument

* proc.c (rb_iseq_min_max_arity): maximum argument is unlimited if
  having rest keywords argument.  [ruby-core:53298] [Bug #8072]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@44413 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
iseq.c: fix parameter of unnamed rest keywords argument

* iseq.c (rb_iseq_parameters): push argument type symbol only for
  unnamed rest keywords argument.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@44414 b2dd03c8-39d4-4d8f-98ff-823fe69b080e