The async vhost callback ops should return negative value when there
are something wrong in the callback, so the return type should be
changed into int32_t. The issue in vhost example is also fixed.
Fixes: cd6760da1076 ("vhost: introduce async enqueue for split ring")
Fixes: 819a71685826 ("vhost: fix async callback return type")
Fixes: 6b3c81db8bb7 ("vhost: simplify async copy completion")
Fixes: abec60e7115d ("examples/vhost: support vhost async data path")
Fixes: 6e9a9d2a02ae ("examples/vhost: fix ioat dependency")
Fixes: 873e8dad6f49 ("vhost: support packed ring in async datapath")
Cc: stable@dpdk.org
Signed-off-by: Cheng Jiang <cheng1.jiang@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
3f63c19b2b