CONFIG_SH_MTU2 is not available for thedefaultarchitecture x86.
Result is shown for architecture sh
default or selected kernelversion does not have config value CONFIG_SH_MTU2.
Result is shown for kernelversion 5.3.7

MTU2 timer support

modulename: timer-mtu2.ko

configname: CONFIG_SH_MTU2

Linux/SuperH Kernel Configuration
└─>System type
└─>Timer and clock configuration
└─>MTU2 timer support
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
This enables the use of the MTU2 as the system timer.

source code:
depends
CONFIG_CPU_SH2A