hwmon: (pwm-fan) Replace OF specific call to PWM by plain one

hwmon: (pwm-fan) Replace OF specific call to PWM by plain one

There is no need to call OF specific devm_of_pwm_get() since
the device node parameter duplicates in the device parameter.
Hence we may safely replace it by plain devm_pwm_get() call.

This allows to drop devm_of_pwm_get() as no more users will be.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220826172642.16404-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>