[SCSI] iscsi: fix 2.6.19 data digest calculation bug

The transition from crypto_digest_*() to  the crypto_hash_*() family
introduced a bug into the data digest calculation: crypto_hash_update() is
called with the number of S/G elements instead of the S/G lists data size.
Signed-off-by: NArne Redlich <arne.redlich@xiranet.com>
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

drivers/scsi/iscsi_tcp.c

@@ -749,7 +749,7 @@ static int iscsi_scsi_data_in(struct iscsi_conn *conn)
 				if (!offset)
 					crypto_hash_update(
 							&tcp_conn->rx_hash,
-							&sg[i], 1);
+							&sg[i], sg[i].length);
 				else
 					partial_sg_digest_update(
 							&tcp_conn->rx_hash,