vhost: prevent zero-copy with incompatible client mode

vhost: prevent zero-copy with incompatible client mode

In server mode, virtio-user inits under the assumption that vhost-user
supports a list of features. However, this could be problematic when
in_order feature is negotiated but not supported by vhost-user when
enables dequeue_zero_copy later.

Add handling when vhost-user enables dequeue_zero_copy as client.

Fixes: 64ab701c3d1e ("vhost: add vhost-user client mode")
Cc: stable@dpdk.org
Signed-off-by: Xuan Ding <xuan.ding@intel.com>
Tested-by: Yinan Wang <yinan.wang@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>