default or selected kernelversion does not have config value CONFIG_CRYPTO_FPU.
Result is shown for kernelversion 5.4.69

CONFIG_CRYPTO_FPU (not configurable)

modulename: fpu.ko

configname: CONFIG_CRYPTO_FPU

Linux Kernel Configuration
└─>Cryptographic API
└─>CRYPTO_FPU
In linux kernel since version 2.6.31 (release Date: 2009-09-09)  
source code:
arch/x86/crypto/fpu.c

depends
CONFIG_CRYPTO