cmake HAVE_SYS_DEVPOLL_H examples

alibaba/AliSQL configure.cmake :417 

CHECK_INCLUDE_FILES(sys/devpoll.h HAVE_SYS_DEVPOLL_H)

alibaba/AliSQLBackup configure.cmake :333 

CHECK_INCLUDE_FILES(sys/devpoll.h HAVE_SYS_DEVPOLL_H)