cmake HAVE_PTHREAD_RWLOCK_RDLOCK examples

arkdb/inception configure.cmake :451 

CHECK_FUNCTION_EXISTS (pthread_rwlock_rdlock HAVE_PTHREAD_RWLOCK_RDLOCK)

alibaba/AliSQL configure.cmake :558 

CHECK_FUNCTION_EXISTS (pthread_rwlock_rdlock HAVE_PTHREAD_RWLOCK_RDLOCK)

Tokutek/mysql-5.5 configure.cmake :391 

CHECK_FUNCTION_EXISTS (pthread_rwlock_rdlock HAVE_PTHREAD_RWLOCK_RDLOCK)