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

CONFIG_PPC_INDIRECT_MMIO (not configurable)

configname: CONFIG_PPC_INDIRECT_MMIO

Linux Kernel Configuration
└─>Platform support
└─>PPC_INDIRECT_MMIO
In linux kernel since version 3 (release Date: 2011-07-21)  
is depended by
CONFIG_PPC_ISERIES