CONFIG_CPU_NEED_SOFTALIGN is not available for thedefaultarchitecture x86.
Result is shown for architecture csky

CONFIG_CPU_NEED_SOFTALIGN (not configurable)

modulename: alignment.ko

configname: CONFIG_CPU_NEED_SOFTALIGN

Linux Kernel Configuration
└─>CPU_NEED_SOFTALIGN
In linux kernel since version 4.2 (release Date: 2015-08-30)  
source code:
arch/csky/abiv1/alignment.c