Remove superfluous define of _XOPEN_SOURCE.
Remove superfluous define of _XOPEN_SOURCE.

jerome-pouiller/reredirect,jerome-pouiller/reredirect,nelhage/reptyr,nelhage/reptyr,nelhage/reptyr,developerfm/reptyr,yatsek/reptyr,developerfm/reptyr,yatsek/reptyr,developerfm/reptyr,yatsek/reptyr