CONFIG_CPU_XLP is not available for thedefaultarchitecture x86.
Result is shown for architecture mips

Netlogic XLP SoC

modulename: pci-xlp.ko

and/or

msi-xlp.ko

configname: CONFIG_CPU_XLP

CPU type
└─>Netlogic XLP SoC
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Netlogic Microsystems XLP processors.

source code:
arch/mips/pci/pci-xlp.c


is selected by
CONFIG_GPIO_XLP