CONFIG_FPU is not available for thedefaultarchitecture x86.
Result is shown for architecture mn10300

FPU present

modulename: fpu-low.ko

and/or

fpu.ko

configname: CONFIG_FPU

Matsushita MN10300/AM33 Kernel Configuration
└─>Matsushita MN10300 system setup
└─>FPU present
In linux kernel since version 2.6.12  
source code:
arch/mn10300/kernel/
depends
CONFIG_MN10300_PROC_MN103E010 or | or CONFIG_MN10300_PROC_MN2WS0050