error.c: remove unused function
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@54620 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
error.c: remove unused function
never been exposed.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@54620 b2dd03c8-39d4-4d8f-98ff-823fe69b080e