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

Allwinner ARMv5 F-series (suniv) SoCs support

configname: CONFIG_MACH_SUNIV

Linux Kernel Configuration
└─>Allwinner SoCs
└─>Allwinner ARMv5 F-series (suniv) SoCs support
In linux kernel since version 5 (release Date: 2019-03-03)  
Support for Allwinner suniv ARMv5 SoCs.
(F1C100A, F1C100s, F1C200s, F1C500, F1C600)