default or selected kernelversion does not have config value CONFIG_REGULATOR_RT5759.
Result is shown for kernelversion 6.9-rc5

Richtek RT5759 Regulator

modulename: rt5759-regulator.ko

configname: CONFIG_REGULATOR_RT5759

Linux Kernel Configuration
└─>Device Drivers
└─>Voltage and Current Regulator Support
└─>Richtek RT5759 Regulator
In linux kernel since version 5.2 (release Date: 2019-07-07)  
This adds support for voltage regulator in Richtek RT5759.
The RT5759 is a high-performance, synchronous step-down DC-DC
converter that can deliver up to 9A output current from 3V to 6.5V
input supply.

source code:
drivers/regulator/rt5759-regulator.c