Revert "hwmon: (ibmpex) fix use-after-free in high/low store"

Revert "hwmon: (ibmpex) fix use-after-free in high/low store"

This reverts commit 6946c726c3f4c36f0f049e6f97e88c510b15f65d.

Jean Delvare points out that the patch does not completely
fix the reported problem, that it in fact introduces a
(new) race condition, and that it may actually not be needed in
the first place.

Various AI reviews agree. Specific and relevant AI feedback:

"
This reordering sets the driver data to NULL before removing the sensor
attributes in the loop below.

ibmpex_show_sensor() retrieves this driver data via dev_get_drvdata() but
does not check if it is NULL before dereferencing it to access
data->sensors[].

If a userspace process reads a sensor file (like temp1_input) while this
delete function is running, could it race with the dev_set_drvdata(...,
NULL) call here and crash in ibmpex_show_sensor()?

Would it be safer to keep the original order where device_remove_file() is
called before clearing the driver data? device_remove_file() should wait
for any active sysfs callbacks to complete, which might already prevent the
use-after-free this patch intends to fix.
"

Revert the offending patch. If it can be shown that the originally reported
alleged race condition does indeed exist, it can always be re-introduced
with a complete fix.

Reported-by: Jean Delvare <jdelvare@suse.de>
Closes: https://lore.kernel.org/linux-hwmon/20260121095342.73e723cb@endymion/
Cc: Jean Delvare <jdelvare@suse.de>
Cc: Junrui Luo <moonafterrain@outlook.com>
Fixes: 6946c726c3f4 ("hwmon: (ibmpex) fix use-after-free in high/low store")
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>