cmake HAVE_TIMERCLEAR examples

mongodb/mongo-bi-connector-odbc-driver configure.cmake :512 

CHECK_SYMBOL_EXISTS (timerclear "sys/time.h" HAVE_TIMERCLEAR)

alibaba/AliSQL configure.cmake :630 

CHECK_SYMBOL_EXISTS (timerclear "sys/time.h" HAVE_TIMERCLEAR)

alibaba/AliSQLBackup configure.cmake :545 

CHECK_SYMBOL_EXISTS (timerclear "sys/time.h" HAVE_TIMERCLEAR)