hwmon: (dell-smm-hwmon) Use devm_add_action_or_reset()

Use devm_add_action_or_reset() for calling i8k_exit_procfs()
so the remove() function in dell_smm_driver can be omitted.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Reviewed-by: Pali Rohár <pali@kernel.org>
Tested-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20210728221557.8891-4-W_Armin@gmx.de


Signed-off-by: Guenter Roeck <linux@roeck-us.net>