Enable the firmware sysfs fallback mechanism

configname: CONFIG_FW_LOADER_USER_HELPER

Linux Kernel Configuration
└─>Device Drivers
└─>Generic Driver Options
└─>Firmware loader
└─>Enable the firmware sysfs fallback mechanism
In linux kernel since version 3.1 (release Date: 2011-10-24)  
This option enables a sysfs loading facility to enable firmware
loading to the kernel through userspace as a fallback mechanism
if and only if the kernel's direct filesystem lookup for the
firmware failed using the different /lib/firmware/ paths, or the
path specified in the firmware_class path module parameter, or the
firmware_class path kernel boot parameter if the firmware_class is
built-in. For details on how to work with the sysfs fallback mechanism
refer to