test_file_exhaustive.rb: remove useless assignment

	* test/ruby/test_file_exhaustive.rb (make_tmp_filename): not
  assign to instance variable, @hardlinkfile.
	* file.c (rb_file_identical_p): fix handle leak, ensure to close
	  the handle of the first argument.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_2@49677 b2dd03c8-39d4-4d8f-98ff-823fe69b080e