CONFIG_MACH_SPEAR310 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

SPEAr310 Machine support with Device Tree

modulename: spear310.ko

configname: CONFIG_MACH_SPEAR310

Linux Kernel Configuration
└─>SPEAr3xx Implementations
└─>SPEAr310 Machine support with Device Tree
In linux kernel since version 2.6.35 (release Date: 2010-08-01)  
Supports ST SPEAr310 machine configured via the device-tree

source code: