Revert accidental cleanup.

Alexey Zaytsev points out that lyx automatically changes some of the
formatting when saving (perhaps a manual edit previously?).  Simply re-saving
the file causes this to change; doing it now avoids pointless diffs.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Document VIRTIO_BLK_T_GET_ID

Signed-off-by: Alexey Zaytsev <alexey.zaytsev@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>