CONFIG_ARM_SINGLE_ARMV7M is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

CONFIG_ARM_SINGLE_ARMV7M (not configurable)

configname: CONFIG_ARM_SINGLE_ARMV7M

Linux Kernel Configuration
└─>System Type
└─>ARM_SINGLE_ARMV7M
In linux kernel since version 3.10 (release Date: 2013-06-30)  

depends
 or  NOT CONFIG_MMU

is selected by
CONFIG_ARCH_EFM32