CONFIG_PPC_MULTIPLATFORM is not available for thedefaultarchitecture x86.
Result is shown for architecture powerpc
Generic desktop/server/laptop
modulename: prom_init.ko
configname: CONFIG_PPC_MULTIPLATFORM
Machine type
└─>Generic desktop/server/laptop
In linux kernel since version 2.6.15 (release Date: 2006-01-02)
Select this option if configuring for an IBM pSeries or
RS/6000 machine, an Apple machine, or a PReP, CHRP,
Maple or Cell-based machine.
RS/6000 machine, an Apple machine, or a PReP, CHRP,
Maple or Cell-based machine.