lguest: Fix lguest virtio-blk backend size computation

This seems like an obvious typo but it's worked in the past because the virtio
blk frontend just ignores the length field on completion.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
1 file changed