CONFIG_SH_FPU is not available for the selected architecture x86.
Result is shown for architecture sh

FPU support

modulename: fpu.ko

configname: CONFIG_SH_FPU

Linux Kernel Configuration
└─>Processor features
└─>FPU support
In linux kernel since version 2.6.12 )
Selecting this option will enable support for SH processors that
have FPU units (ie, SH77xx).

This option must be set in order to enable the FPU.
source code:
arch/sh/kernel/cpu/sh2a/fpu.c