CONFIG_476FPE is not available for thedefaultarchitecture x86.
Result is shown for architecture powerpc

CONFIG_476FPE (not configurable)

configname: CONFIG_476FPE

Linux Kernel Configuration
└─>476FPE
In linux kernel since version 3.1 (release Date: 2011-10-24)  
selects
CONFIG_PPC_FPU

is depended by
CONFIG_FSP2
CONFIG_AKEBONO