CONFIG_CRYPTO_SHA256_SPARC64 is not available for thedefaultarchitecture x86.
Result is shown for architecture sparc or 64BIT

CONFIG_CRYPTO_SHA256_SPARC64 (not configurable)

modulename: sha256-sparc64.ko

configname: CONFIG_CRYPTO_SHA256_SPARC64

Linux Kernel Configuration
└─>CRYPTO_SHA256_SPARC64
In linux kernel since version 3.1 (release Date: 2011-10-24)  
source code:
/arch/sparc/lib/crypto/

depends
CONFIG_SPARC64