virtio-net: support the virtqueue coalescing moderation

[hengqiali]

Currently, coalescing parameters are grouped for all transmit and receive
virtqueues. This patch supports setting or getting the parameters for a
specified virtqueue, and a typical application of this function is netdim[1].

When the traffic between virtqueues is unbalanced, for example, one virtqueue
is busy and another virtqueue is idle, then it will be very useful to
control coalescing parameters at the virtqueue granularity.

[1] https://docs.kernel.org/networking/net_dim.html

Patch: https://lists.oasis-open.org/archives/virtio-dev/202303/msg00415.html

[mstsirkin]

BALLOT CREATED AT URL: https://www.oasis-open.org/committees/ballot.php?id=3767

[hengqiali]

Hi chairs, I have updated the issue description with the latest patch link:
https://lists.oasis-open.org/archives/virtio-dev/202303/msg00415.html

[cohuck]

BALLOT CREATED AT URL: https://www.oasis-open.org/committees/ballot.php?id=3768