CONFIG_SH_LBOX_RE2 is not available for thedefaultarchitecture x86.
Result is shown for architecture sh

L-BOX RE2

modulename: ops-lboxre2.ko

and/or

fixups-rts7751r2d.ko

configname: CONFIG_SH_LBOX_RE2

Linux/SuperH Kernel Configuration
└─>System type
└─>Board support
└─>L-BOX RE2
In linux kernel since version 2.6.22 (release Date: 2007-07-08)  
Select L-BOX RE2 if configuring for the NTT COMWARE L-BOX RE2.

source code:
/arch/sh/drivers/pci/