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

CSR SiRFSoC power on/off/suspend key support

modulename: sirfsoc-onkey.ko

configname: CONFIG_INPUT_SIRFSOC_ONKEY

Linux Kernel Configuration
└─>Device Drivers
└─>Input device support
└─>Miscellaneous devices
└─>Device Tree and Open Firmware support
└─>CSR SiRFSoC power on/off/suspend key support
In linux kernel since version 3.11 (release Date: 2013-09-02)  
Say Y here if you want to support for the SiRFSoC power on/off/suspend key
in Linux, after you press the onkey, system will suspend.

If unsure, say N.

source code: