REDHAT-BUG-2529666: Medium severity DPDK lib/vhost vulnerability

A flaw was found in DPDK lib/vhost. The vhost-user SETMEMTABLE mmap path does not adequately validate frontend-supplied region size before mapping, which may lead to denial of service in the host vhost backend. Integer-overflow and zero-size-after-align checks are already present; the remaining size check is as reported by the DPDK vhost maintainer.