default or selected kernelversion does not have config value CONFIG_SYS_R9A09G056.
Result is shown for kernelversion 6.16-rc7

Renesas RZ/V2N System controller support

modulename: r9a09g056-sys.ko

configname: CONFIG_SYS_R9A09G056

Linux Kernel Configuration
└─>Device Drivers
└─>SOC (System On Chip) specific Drivers
└─>Renesas SoC driver support
└─>Renesas RZ/V2N System controller support
In linux kernel since version 6.1.145 (release Date: 2025-07-14)  
source code:
drivers/soc/renesas/r9a09g056-sys.c
selects
CONFIG_SYSC_RZ


is depended by
CONFIG_ARCH_R9A09G056