IB/mlx5: Fix error code in get_port_caps()

The current code returns success when kmalloc() fails.  It should
return an error code, -ENOMEM.

Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/hw/mlx5/main.c

@@ -997,7 +997,7 @@ static int get_port_caps(struct mlx5_ib_dev *dev)
 	struct ib_device_attr *dprops = NULL;
 	struct ib_port_attr *pprops = NULL;
 	struct mlx5_general_caps *gen;
-	int err = 0;
+	int err = -ENOMEM;
 	int port;
 
 	gen = &dev->mdev->caps.gen;