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

CONFIG_NLM_XLR (not configurable)

modulename: pci-xlr.ko

configname: CONFIG_NLM_XLR

Linux Kernel Configuration
└─>NLM_XLR
In linux kernel since version 3 (release Date: 2011-07-21)  
source code:
arch/mips/pci/pci-xlr.c