CONFIG_ARCH_RPC is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
RiscPC
configname: CONFIG_ARCH_RPC
ARM system type
└─>RiscPC
In linux kernel since version 2.6.12
On the Acorn Risc-PC, Linux can support the internal IDE disk and
CD-ROM interface, serial and parallel port, and the floppy drive.
CD-ROM interface, serial and parallel port, and the floppy drive.