default or selected kernelversion does not have config value CONFIG_CLK_R8A7796.
Result is shown for kernelversion 6.9.9

R-Car M3-W clock support

modulename: r8a7796-cpg-mssr.ko

configname: CONFIG_CLK_R8A7796

Linux Kernel Configuration
└─>Device Drivers
└─>Common Clock Framework
└─>R-Car M3-W clock support
In linux kernel since version 3.10 (release Date: 2013-06-30)  
source code:
drivers/clk/renesas/r8a7796-cpg-mssr.c