cciss: Add missing allocation in scsi_cmd_stack_setup and corresponding deallocation

This bit got lost somewhere along the way.  Without this, panic.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

drivers/block/cciss_scsi.c

@@ -226,6 +226,13 @@ scsi_cmd_stack_setup(ctlr_info_t *h, struct cciss_scsi_adapter_data_t *sa)
 		return -ENOMEM;
 	}
 
+	stk->elem = kmalloc(sizeof(stk->elem[0]) * stk->nelems, GFP_KERNEL);
+	if (!stk->elem) {
+		pci_free_consistent(h->pdev, size, stk->pool,
+		stk->cmd_pool_handle);
+		return -1;
+	}
+
 	for (i=0; i<CMD_STACK_SIZE; i++) {
 		stk->elem[i] = &stk->pool[i];
 		stk->elem[i]->busaddr = (__u32) (stk->cmd_pool_handle + 
@@ -255,6 +262,8 @@ scsi_cmd_stack_free(ctlr_info_t *h)
 	pci_free_consistent(h->pdev, size, stk->pool, stk->cmd_pool_handle);
 	stk->pool = NULL;
 	cciss_free_sg_chain_blocks(sa->cmd_sg_list, CMD_STACK_SIZE);
+	kfree(stk->elem);
+	stk->elem = NULL;
 }
 
 #if 0