virtio: clean up features qword/dword terms

virtio: clean up features qword/dword terms

[ Upstream commit 9513f25056b22100ddffe24898c587873b0d022c ]

virtio pci uses word to mean "16 bits". mmio uses it to mean
"32 bits".

To avoid confusion, let's avoid the term in core virtio
altogether. Just say U64 to mean "64 bit".

Fixes: e7d4c1c5a546 ("virtio: introduce extended features")
Cc: Paolo Abeni <pabeni@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-ID: <ad53b7b6be87fc524f45abaeca0bb05fb3633397.1764225384.git.mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>