CONFIG_PPC_86xx is not available for thedefaultarchitecture x86.
Result is shown for architecture powerpc

Freescale 86xx

configname: CONFIG_PPC_86xx

Machine type
└─>Freescale 86xx
In linux kernel since version 2.6.18 (release Date: 2006-09-19)  
The Freescale E600 SoCs have 74xx cores.