CONFIG_PPC_STD_MMU is not available for thedefaultarchitecture x86.
Result is shown for architecture powerpc

CONFIG_PPC_STD_MMU (not configurable)

configname: CONFIG_PPC_STD_MMU

Linux Kernel Configuration
└─>Processor support
└─>PPC_STD_MMU
In linux kernel since version 2.6.15 (release Date: 2006-01-02)