bnge: Fix NULL pointer dereference in aux device release

bnge: Fix NULL pointer dereference in aux device release

If allocation of auxr_dev fails during auxiliary device setup, the error
path calls auxiliary_device_uninit(), which eventually invokes
bnge_aux_dev_release().

The release callback unconditionally dereferences aux_priv->auxr_dev->pdev
to retrieve the parent bnge_dev. Since auxr_dev has not yet been allocated
on this failure path, the dereference results in a NULL pointer exception

Retrieve the parent bnge_dev from the auxiliary device's parent instead of
auxr_dev, and free auxr_dev only when it was successfully allocated. This
allows the release callback to correctly clean up partially initialized
auxiliary devices.

Fixes: 8ac050ec3b1c ("bng_en: Add RoCE aux device support")
Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
Reviewed-by: Bhargava Marreddy <bhargava.marreddy@broadcom.com>
Link: https://patch.msgid.link/20260731192301.1427645-1-alok.a.tiwari@oracle.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>