cmake HAVE_PTHREAD_KEY_DELETE examples

arkdb/inception configure.cmake :450 

CHECK_FUNCTION_EXISTS (pthread_key_delete HAVE_PTHREAD_KEY_DELETE)

alibaba/AliSQL configure.cmake :557 

CHECK_FUNCTION_EXISTS (pthread_key_delete HAVE_PTHREAD_KEY_DELETE)

Tokutek/mysql-5.5 configure.cmake :390 

CHECK_FUNCTION_EXISTS (pthread_key_delete HAVE_PTHREAD_KEY_DELETE)