CONFIG_SYS_SUPPORTS_MTU2 is not available for thedefaultarchitecture x86.
Result is shown for architecture sh

CONFIG_SYS_SUPPORTS_MTU2 (not configurable)

configname: CONFIG_SYS_SUPPORTS_MTU2

Linux/SuperH Kernel Configuration
└─>SYS_SUPPORTS_MTU2
In linux kernel since version 2.6.31 (release Date: 2009-09-09)