When auxiliary_device_add() returns error and then calls
auxiliary_device_uninit(), callback function adev_release
calls kfree(madev). We shouldn't call kfree(madev) again
in the error handling path. Set 'madev' to NULL.

Signed-off-by: Ma Ke <redacted>
---
Changes in v2:
- streamlined the patch according suggestions;
- revised the description.
---
  drivers/net/ethernet/microsoft/mana/mana_en.c | 2 ++
  1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index d087cf954f75..608ad31a9702 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c

@@ -2798,6 +2798,8 @@ static int add_adev(struct gdma_dev *gd)
  	if (ret)
  		goto init_fail;
  
+	/* madev is owned by the auxiliary device */
+	madev = NULL;
  	ret = auxiliary_device_add(adev);
  	if (ret)
  		goto add_fail;