I wrote two changes [1] for passing down target allocations to virt drivers given we need to use them for closing some bugfix [2]

Given the Nova contributor policy is saying that the public API is not related to virt drivers, we won't support virt drivers that won't accept this new argument.

If you're a contributor that works on any out-of-tree Nova virt driver, please make sure that you modify your own two above methods.

Thanks,
-Sylvain

[1] https://review.opendev.org/#/c/589085/7 and https://review.opendev.org/#/c/712118/2
[2] https://bugs.launchpad.net/nova/+bug/1778563