CONFIG_LUAN is not available for thedefaultarchitecture x86.
Result is shown for architecture ppc

Luan

modulename: luan.ko

and/or

pci_auto.ko

configname: CONFIG_LUAN

Machine Type
└─>Luan
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
This option enables support for the IBM PPC440SP evaluation board.

source code:
arch/ppc/platforms/4xx/luan.c