OvmfPkg/VirtioMmioDeviceLib: Add virtio 1.0 detection.

Add #defines for the Version field.  Read and store the version,
log the version found as info message.

Continue to return UNSUPPORTED for now, we need some more patches
to complete virtio 1.0 support first.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>

OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.h

@@ -23,9 +23,13 @@
 #include <Library/MemoryAllocationLib.h>
 
 #define VIRTIO_MMIO_DEVICE_SIGNATURE  SIGNATURE_32 ('V', 'M', 'I', 'O')
+#define VIRTIO_MMIO_DEVICE_VERSION_0_95  1
+#define VIRTIO_MMIO_DEVICE_VERSION_1_00  2
+
 
 typedef struct {
   UINT32                 Signature;
+  UINT32                 Version;
   VIRTIO_DEVICE_PROTOCOL VirtioDevice;
   PHYSICAL_ADDRESS       BaseAddress;
 } VIRTIO_MMIO_DEVICE;