CONFIG_ACPI_CPU_FREQ_PSS (not configurable)

configname: CONFIG_ACPI_CPU_FREQ_PSS

Linux Kernel Configuration
└─>Power management and ACPI options
└─>ACPI (Advanced Configuration and Power Interface) Support
└─>ACPI_CPU_FREQ_PSS
In linux kernel since version 4.2 (release Date: 2015-08-30)  
selects
CONFIG_THERMAL

depends
CONFIG_ACPI

is depended by
CONFIG_ACPI_PROCESSOR