cmake HAVE_ATTR_SYMVER examples

ceph/ceph cmake/modules/CephChecks.cmake :171

check_c_source_compiles("
__attribute__((__symver__ (\"func@v1\"))) void func_v1() {};
__attribute__((__symver__ (\"func@v2\"))) void func_v2() {};

int main() {}"
  HAVE_ATTR_SYMVER)