Add Return and (where interesting) Context sections, fix some formatting
and drop documenting the internal function __pwm_apply().
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/20250417181611.2693599-2-u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>