hwmon: (lm83) Remove unused include directives

hwmon: (lm83) Remove unused include directives

Some include directives are no longer necessary due to previous driver
changes. Remove them now to further improve driver code clarity.

Mutex usage has ceased since commit 719af4f1a40b ("hwmon: (lm83) Use
regmap").

Ever since commit a0ac840d99fa ("hwmon: (lm83) Convert to use
devm_hwmon_device_register_with_groups") functions sysfs_create_group
and sysfs_remove_group are no longer used by the driver.

Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
Link: https://lore.kernel.org/r/20220508144601.22796-1-kmehltretter@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>