s390 zfcp: sg fixups

Based on initial patch from Heiko Carstens <heiko.carstens@de.ibm.com>

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index 7507067..fd5d0c1 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -559,6 +559,7 @@
 		retval = -ENOMEM;
 		goto out;
 	}
+	sg_init_table(sg_list->sg, sg_list->count);
 
 	for (i = 0, sg = sg_list->sg; i < sg_list->count; i++, sg++) {
 		sg->length = min(size, PAGE_SIZE);