CONFIG_ARCH_R8A7790 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

R-Car H2 (R8A77900)

modulename: setup-r8a7790.ko

and/or

clock-r8a7790.ko

and/or

clk-rcar-gen2.ko

configname: CONFIG_ARCH_R8A7790

Linux Kernel Configuration
└─>R-Car H2 (R8A77900)
In linux kernel since version 3.1 (release Date: 2011-10-24)  
source code:
arch/arm/mach-shmobile/setup-r8a7790.c