CONFIG_SOC_IMX6SL is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

i.MX6 SoloLite support

modulename: mach-imx6sl.ko

and/or

cpuidle-imx6sl.ko

and/or

clk-imx6sl.ko

configname: CONFIG_SOC_IMX6SL

Linux Kernel Configuration
└─>Freescale i.MX support
└─>i.MX6 SoloLite support
In linux kernel since version 3.10 (release Date: 2013-06-30)  
This enables support for Freescale i.MX6 SoloLite processor.

source code:
/arch/arm/mach-imx/


is selected by
CONFIG_PINCTRL_IMX6SL