virtio-net: clarify coalescing parameters settings

[hengqiali]

The device can set any initial coalescing parameters (0 or non-zero)
for the receive/send queue before the setting command is executed,
not just 0, enhancing device performance even without DIM enabled.

So we need to clarify descriptions that don't fit the behavior.

Solution: https://lore.kernel.org/virtio-comment/87le3qmibk.fsf@redhat.com/T/#m03c7ae7c9f605db32078ce04283f5175c17518d2

[mstsirkin]

the link point to review, pls fix it to point at the proposal itself, and we'll vote

[hengqiali]

the link point to review, pls fix it to point at the proposal itself, and we'll vote

Fixed.

[mstsirkin]

BALLOT CREATED AT URL: https://groups.oasis-open.org/higherlogic/ws/public/ballot?id=3834