[PATCH v2 -next] IB/mlx5: Add missing error code

[YueHaibing]

Set err to -ENOMEM if kzalloc fails instead of 0.

Fixes: 759738537142 ("IB/mlx5: Enable subscription for device events over DEVX")
Signed-off-by: YueHaibing <yuehaib...@huawei.com>
---
 drivers/infiniband/hw/mlx5/devx.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/hw/mlx5/devx.c 
b/drivers/infiniband/hw/mlx5/devx.c
index ebc2a4355fa5..3c8e6a25465d 100644
--- a/drivers/infiniband/hw/mlx5/devx.c
+++ b/drivers/infiniband/hw/mlx5/devx.c
@@ -2073,8 +2073,10 @@ static int 
UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT)(
 
                num_alloc_xa_entries++;
                event_sub = kzalloc(sizeof(*event_sub), GFP_KERNEL);
-               if (!event_sub)
+               if (!event_sub) {
+                       err = -ENOMEM;
                        goto err;
+               }
 
                list_add_tail(&event_sub->event_list, &sub_list);
                uverbs_uobject_get(&ev_file->uobj);
-- 
2.20.1