CONFIG_ARCH_MXC_IOMUX_V3 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

CONFIG_ARCH_MXC_IOMUX_V3 (not configurable)

modulename: iomux-v3.ko

configname: CONFIG_ARCH_MXC_IOMUX_V3

Linux Kernel Configuration
└─>Freescale i.MX family
└─>ARCH_MXC_IOMUX_V3
In linux kernel since version 2.6.31 (release Date: 2009-09-09)  
source code:
arch/arm/mach-imx/iomux-v3.c
depends
CONFIG_ARCH_MXC

is depended by
CONFIG_SOC_IMX25