* configure.in: move header files check to the beginning of
  "header and library section".
  test rlim_t with sys/types.h and sys/time.h for MirOS BSD.
  sys/types.h and sys/time.h is gurded by #ifdef and the above move
  is required for this change.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39174 b2dd03c8-39d4-4d8f-98ff-823fe69b080e