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

Sunplus SoCs

configname: CONFIG_ARCH_SUNPLUS

Linux Kernel Configuration
└─>Sunplus SoCs
In linux kernel since version 6 (release Date: 2022-10-02)  
Support for Sunplus SoC family: SP7021 and succeeding SoC-based systems,
such as the Banana Pi BPI-F2S development board (and derivatives).
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