[SCSI] fix sense buffer length handling problem

The new bio code was incorrectly converted from stack allocated to
kmalloc'd buffer handling.  There are two places where it incorrectly
uses sizeof(*sense) to get the size of the sense buffer.  This
actually produces one, so no sense data was ever getting back, causing
failure in things like disk spin up.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

drivers/scsi/scsi_lib.c

@@ -342,12 +342,12 @@ int scsi_execute_req(struct scsi_device *sdev, const unsigned char *cmd,
 		sense = kmalloc(SCSI_SENSE_BUFFERSIZE, GFP_KERNEL);
 		if (!sense)
 			return DRIVER_ERROR << 24;
-		memset(sense, 0, sizeof(*sense));
+		memset(sense, 0, SCSI_SENSE_BUFFERSIZE);
 	}
 	result = scsi_execute(sdev, cmd, data_direction, buffer, bufflen,
 				  sense, timeout, retries, 0);
 	if (sshdr)
-		scsi_normalize_sense(sense, sizeof(*sense), sshdr);
+		scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, sshdr);
 
 	kfree(sense);
 	return result;