CONFIG_CPU_BIG_ENDIAN is not available for the selected architecture x86.
Result is shown for architecture mips

Big endian

modulename: sniprom.ko

configname: CONFIG_CPU_BIG_ENDIAN

Endianess selection
└─>Big endian
In linux kernel since version 2.6.12 )
source code:
arch/mips/sni/sniprom.c


is depended by
CONFIG_ARC_PLAT_EZNPS