CONFIG_8260 is not available for thedefaultarchitecture x86.
Result is shown for architecture powerpc

CONFIG_8260 (not configurable)

configname: CONFIG_8260

Linux Kernel Configuration
└─>8260
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
The MPC8260 is a typical embedded CPU made by Freescale. Selecting
this option means that you wish to build a kernel for a machine with
an 8260 class CPU.