regulator: pf9453: Improve documentation for pf9453_regulator_set_ramp_delay_regmap

The function pf9453_regulator_set_ramp_delay_regmap lacked detailed
parameter descriptions and return value explanations in its documentation.
This patch improves the documentation by adding specific details about
the parameters, their usage, and the return values, enhancing clarity for
developers.

Reported-by: Abaci Robot <[email protected]>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=20168
Signed-off-by: Yang Li <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>

Author: Yang Li

drivers/regulator/pf9453-regulator.c

@@ -412,6 +412,7 @@ static int find_closest_bigger(unsigned int target, const unsigned int *table,
  * pf9453_regulator_set_ramp_delay_regmap
  *
  * @rdev: regulator to operate on
+ * @ramp_delay: desired ramp delay value in microseconds
  *
  * Regulators that use regmap for their register I/O can set the ramp_reg
  * and ramp_mask fields in their descriptor and then use this as their