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

Xilinx FPGA firmware download module

modulename: gs_fpga.ko

configname: CONFIG_GS_FPGABOOT

Linux Kernel Configuration
└─>Device Drivers
└─>Staging drivers
└─>Xilinx FPGA firmware download module
In linux kernel since version 3.15 (release Date: 2014-06-08)  
Xilinx FPGA firmware download module

source code:
depends
CONFIG_STAGING