* ext/etc/etc.c (etc_getpwnam): use PRIsVALUE in format string instead
  of %s and RSTRING_PTR

* ext/etc/etc.c (etc_getgrnam): ditto

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@41558 b2dd03c8-39d4-4d8f-98ff-823fe69b080e