net/vmxnet3: enable on Windows

net/vmxnet3: enable on Windows

Remove OS restriction and update release notes.

For the record, tested on the following setup with Windows Server 2019 in
QEMU (-device vmxnet3) :

[ping     ]           [                     ]           [     ping]
[OS       ]           [    dpdk-skeleton    ]           [       OS]
[virtio---]--sockets--[---vmxnet3 vmxnet3---]--sockets--[---virtio]
[Debian VM]           [     Windows VM      ]           [Debian VM]

Debian VMs successfully ping'd each other with Windows forwarding.

Signed-off-by: Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>
Acked-by: Yong Wang <yongwang@vmware.com>