platform/x86/intel/pmt/discovery: use valid device pointer in dev_err_probe

platform/x86/intel/pmt/discovery: use valid device pointer in dev_err_probe

The PMT feature probe creates a child device with device_create().
If device creation fail, the code pass priv->dev (which is an ERR_PTR)
to dev_err_probe(), which is not a valid device pointer.

This patch change the dev_err_probe() call to use the parent auxiliary
device (&auxdev->dev) and update the error message to reference the
parent device name. It ensure correct error reporting and avoid
passing an invalid device pointer.

Fixes: d9a078809356 ("platform/x86/intel/pmt: Add PMT Discovery driver")
Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
Link: https://patch.msgid.link/20251224095133.115678-1-alok.a.tiwari@oracle.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>