default or selected kernelversion does not have config value CONFIG_IWLWIFI_LEGACY.
Result is shown for kernelversion 6.2.5

CONFIG_IWLWIFI_LEGACY (not configurable)

modulename: iwl-legacy.ko

configname: CONFIG_IWLWIFI_LEGACY

Linux Kernel Configuration
└─>Device Drivers
└─>Network device support
└─>Wireless LAN
└─>IWLWIFI_LEGACY
In linux kernel since version 2.6.39 (release Date: 2011-05-18)  
source code: