CONFIG_PPC44x_SIMPLE is not available for the selected architecture x86.
Result is shown for architecture powerpc
Simple PowerPC 44x board support
modulename: ppc44x_simple.ko
configname: CONFIG_PPC44x_SIMPLE
Linux Kernel Configuration
└─>Simple PowerPC 44x board support
In linux kernel since version 2.6.28 (release Date: 2008-12-24)
This option enables the simple PowerPC 44x platform support.