check for atexit and if not available, leave things into the hand of the compiler
check for atexit and if not available, leave things into the hand of the compiler

git-svn-id: 67bf12f30ddf2081c31403e0b02b2123541f1680@4873 08b3d480-bf2c-0410-a26f-811ee3361c24

adamsdadakaeti/bzflag,khonkhortisan/bzflag,kongr45gpen/bzflag,kongr45gpen/bzflag,khonkhortisan/bzflag,adamsdadakaeti/bzflag,kongr45gpen/bzflag,adamsdadakaeti/bzflag,kongr45gpen/bzflag,adamsdadakaeti/bzflag,kongr45gpen/bzflag,khonkhortisan/bzflag,kongr45gpen/bzflag,kongr45gpen/bzflag,khonkhortisan/bzflag,khonkhortisan/bzflag,adamsdadakaeti/bzflag,khonkhortisan/bzflag,adamsdadakaeti/bzflag,kongr45gpen/bzflag,khonkhortisan/bzflag,adamsdadakaeti/bzflag