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

CONFIG_PPC_CELL (not configurable)

configname: CONFIG_PPC_CELL

Linux Kernel Configuration
└─>PPC_CELL
In linux kernel since version 2.6.15 (release Date: 2006-01-02)  
is selected by
CONFIG_CPU_FREQ_CBE

is depended by
CONFIG_PPC_PS3