virtio: Revert "virtio: find_vqs() add arg sizes"

virtio: Revert "virtio: find_vqs() add arg sizes"

This reverts commit 2c2974a8afede1bc524db8520294c233b2700b61: the
proposed API isn't supported on all transports but no
effort was made to address this.

It might not be hard to fix if we want to: maybe just
rename size to size_hint and make sure legacy
transports ignore the hint.

But it's not sure what the benefit is in any case, so
let's drop it.

Fixes: 2c2974a8afed ("virtio: find_vqs() add arg sizes")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20220816053602.173815-8-mst@redhat.com>