default or selected kernelversion does not have config value CONFIG_WIMAX_I2400M_USB.
Result is shown for kernelversion 6.9.9

Intel Wireless WiMAX Connection 2400 over USB (including 5x50)

modulename: i2400m-usb.ko

configname: CONFIG_WIMAX_I2400M_USB

Linux Kernel Configuration
└─>Device Drivers
└─>Network device support
└─>WiMAX Wireless Broadband devices
└─>Intel Wireless WiMAX Connection 2400 over USB (including 5x50)
In linux kernel since version 2.6.29 (release Date: 2009-03-23)  
Select if you have a device based on the Intel WiMAX
Connection 2400 over USB (like any of the Intel Wireless
WiMAX/WiFi Link 5x50 series).

If unsure, it is safe to select M (module).

source code: