* configure.in (HAVE_STRUCT_STATFS_F_TYPE): check struct statfs.f_type
  to support OpenBSD.

* file.c (statfs_type): use above macro to switch.

* file.c (statfs_inspect): ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45734 b2dd03c8-39d4-4d8f-98ff-823fe69b080e