cciss: handle allocation failure

If kmalloc() fails then cleanup and return failure (-1).

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index ce1a75d..7191c16 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -4718,6 +4718,9 @@
 	h->scatter_list = kmalloc(h->max_commands *
 						sizeof(struct scatterlist *),
 						GFP_KERNEL);
+	if (!h->scatter_list)
+		goto clean4;
+
 	for (k = 0; k < h->nr_cmds; k++) {
 		h->scatter_list[k] = kmalloc(sizeof(struct scatterlist) *
 							h->maxsgentries,