hwmon: (lenovo-ec-sensors): Convert to devm_request_region()

hwmon: (lenovo-ec-sensors): Convert to devm_request_region()

Replace manual request_region()/release_region() with
devm_request_region().  This lets the device-managed framework
handle I/O region lifetime automatically and fixes:

- A double release_region() when probe fails after acquiring the
  I/O region: the probe error path releases it, and then
  lenovo_ec_init() releases it again on the same error path.

- A release-after-use window in lenovo_ec_exit() where
  release_region() was called before platform_device_unregister(),
  leaving the hwmon device active with a released I/O region.

- Missing release_region() in lenovo_ec_probe() if
  devm_hwmon_device_register_with_info() fails.

Remove all four manual release_region() calls that are now handled
automatically and replace request_region with
devm_request_region, use dev_err replace pr_err.

Also remove the now-unnecessary braces around the single-statement
if body.

Fixes: 70118f85e6538 ("hwmon: Add EC Chip driver for Lenovo ThinkStation motherboards")
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Signed-off-by: Kean Ren <rh_king@163.com>
Link: https://lore.kernel.org/r/20260521035228.533317-2-rh_king@163.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>