cmake EVENT__HAVE_DEVPOLL examples

GreatSQL/GreatSQL extra/libevent/libevent-2.1.11-stable/CMakeLists.txt :466 

CHECK_INCLUDE_FILE(sys/devpoll.h EVENT__HAVE_DEVPOLL)

percona/percona-server extra/libevent/libevent-2.1.11-stable/CMakeLists.txt :474 

CHECK_INCLUDE_FILE(sys/devpoll.h EVENT__HAVE_DEVPOLL)

facebook/mysql-5.6 extra/libevent/libevent-2.1.11-stable/CMakeLists.txt :466 

CHECK_INCLUDE_FILE(sys/devpoll.h EVENT__HAVE_DEVPOLL)

polardb/polardbx-engine extra/libevent/libevent-2.1.11-stable/CMakeLists.txt :466 

CHECK_INCLUDE_FILE(sys/devpoll.h EVENT__HAVE_DEVPOLL)

percona/percona-xtradb-cluster extra/libevent/libevent-2.1.11-stable/CMakeLists.txt :466 

CHECK_INCLUDE_FILE(sys/devpoll.h EVENT__HAVE_DEVPOLL)