CONFIG_COLDFIRE is not available for thedefaultarchitecture x86.
Result is shown for architecture m68knommu

CONFIG_COLDFIRE (not configurable)

modulename: clk.ko

configname: CONFIG_COLDFIRE

uClinux/68k (w/o MMU) Kernel Configuration
└─>Processor type and features
└─>COLDFIRE
In linux kernel since version 2.6.12  
source code:
arch/m68knommu/platform/coldfire/