Multiqueue fixes for vhost-vDPA

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2070804.
Brew: https://brewweb.engineering.redhat.com/brew/taskinfo?taskID=45813444
Upstream: Merged.
Test status: Tested by me

This series fixes the multiqueue vhost-vDPA crashes for single queue capable guest.

All patches are cherry-picked.

Signed-off-by: Jason Wang jasowang@redhat.com