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

CONFIG_PPC_NATIVE (not configurable)

configname: CONFIG_PPC_NATIVE

Linux Kernel Configuration
└─>Platform support
└─>PPC_NATIVE
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
Support for running natively on the hardware, i.e. without
a hypervisor. This option is not user-selectable but should
be selected by all platforms that need it.

depends
CONFIG_6xx or CONFIG_PPC64

is depended by
CONFIG_MVME5100