OvmfPkg/Virtio: take RingBaseShift in SetQueueAddress()
For the case when an IOMMU is used for translating system physical
addresses to DMA bus master addresses, the transport-independent
virtio device drivers will be required to map their VRING areas to
bus addresses with VIRTIO_DEVICE_PROTOCOL.MapSharedBuffer() calls.
- MMIO and legacy virtio transport do not support IOMMU to translate the
addresses hence RingBaseShift will always be set to zero.
- modern virtio transport supports IOMMU to translate the address, in
next patch we will update the Virtio10Dxe to use RingBaseShift offset.