CONFIG_SOC_AR2315 is not available for thedefaultarchitecture x86.
Result is shown for architecture mips

Atheros AR2315+ SoC support

modulename: ar2315.ko

configname: CONFIG_SOC_AR2315

Linux Kernel Configuration
└─>Atheros AR2315+ SoC support
In linux kernel since version 3.10 (release Date: 2013-06-30)  
source code:
arch/mips/ath25/ar2315.c
depends
CONFIG_ATH25

is selected by
CONFIG_PCI_AR2315