include/hw/virtio: make some VirtIODevice const

The VirtIODevice structure is not modified in
virtio_vdev_has_feature(). Therefore, make it const
to allow this function to accept const variables.

Signed-off-by: Hawkins Jiawei <yin31149@gmail.com>
Reviewed-by: Eugenio Pérez Martin <eperezma@redhat.com>
Message-Id: <16c0561b921310a32c240a4fb6e8cee3ffee16fe.1685704856.git.yin31149@gmail.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Tested-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

include/hw/virtio/virtio.h

@@ -402,7 +402,7 @@ static inline bool virtio_has_feature(uint64_t features, unsigned int fbit)
     return !!(features & (1ULL << fbit));
 }
 
-static inline bool virtio_vdev_has_feature(VirtIODevice *vdev,
+static inline bool virtio_vdev_has_feature(const VirtIODevice *vdev,
                                            unsigned int fbit)
 {
     return virtio_has_feature(vdev->guest_features, fbit);