virtio: fix feature bit checks

Several places check against the feature bit number instead of against
the feature bit. Fix them.

Cc: qemu-stable@nongnu.org
Reported-by: NThomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
(cherry picked from commit 91d5c57a)
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

hw/scsi/virtio-scsi.c

@@ -144,7 +144,7 @@ static int virtio_scsi_parse_req(VirtIOSCSIReq *req,
      *
      * TODO: always disable this workaround for virtio 1.0 devices.
      */
-    if ((vdev->guest_features & VIRTIO_F_ANY_LAYOUT) == 0) {
+    if ((vdev->guest_features & (1 << VIRTIO_F_ANY_LAYOUT)) == 0) {
         req_size = req->elem.out_sg[0].iov_len;
         resp_size = req->elem.in_sg[0].iov_len;
     }

hw/virtio/dataplane/vring.c

@@ -133,12 +133,12 @@ bool vring_should_notify(VirtIODevice *vdev, Vring *vring)
      * interrupts. */
     smp_mb();
 
-    if ((vdev->guest_features & VIRTIO_F_NOTIFY_ON_EMPTY) &&
+    if ((vdev->guest_features & (1 << VIRTIO_F_NOTIFY_ON_EMPTY)) &&
         unlikely(vring->vr.avail->idx == vring->last_avail_idx)) {
         return true;
     }
 
-    if (!(vdev->guest_features & VIRTIO_RING_F_EVENT_IDX)) {
+    if (!(vdev->guest_features & (1 << VIRTIO_RING_F_EVENT_IDX))) {
         return !(vring->vr.avail->flags & VRING_AVAIL_F_NO_INTERRUPT);
     }
     old = vring->signalled_used;