platform/x86: thinkpad_acpi: Move HWMON initialization to tpacpi_hwmon_pdriver's...

platform/x86: thinkpad_acpi: Move HWMON initialization to tpacpi_hwmon_pdriver's probe

Let the driver core manage the lifetime of the HWMON device, by
registering it inside tpacpi_hwmon_pdriver's probe and using
devm_hwmon_device_register_with_groups().

Signed-off-by: Kurt Borja <kuurtb@gmail.com>
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Tested-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20250215000302.19753-3-kuurtb@gmail.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>