CONFIG_ARCH_R8A774C0 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm64
Renesas RZ/G2E SoC Platform
configname: CONFIG_ARCH_R8A774C0
Linux Kernel Configuration
└─>Platform selection
└─>Renesas RZ/G2E SoC Platform
In linux kernel since version 4.2 (release Date: 2015-08-30)
This enables support for the Renesas RZ/G2E SoC.