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

CONFIG_ACPI_VIOT (not configurable)

modulename: viot.ko

configname: CONFIG_ACPI_VIOT

Linux Kernel Configuration
└─>Power management and ACPI options
└─>ACPI (Advanced Configuration and Power Interface) Support
└─>ACPI_VIOT
In linux kernel since version 5.2 (release Date: 2019-07-07)  
source code:
drivers/acpi/viot.c
depends
CONFIG_ACPI

is depended by
CONFIG_VIRTIO_IOMMU