Actually invoke free() in ut_allocator::deallocate().
Actually invoke free() in ut_allocator::deallocate().

The necessary call was inadvertently commented out in a
merge of MySQL 5.7.14 to MariaDB 10.2.1
(commit fec844aca88e1c6b9c36bb0b811e92d9d023ffb9).

natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2